Encoding multi-media content for a centralized digital video storage system

ABSTRACT

A method begins with a processing module of a centralized digital video storage (DVS) system regarding recording of multi-media content that is to be broadcast at a particular broadcast time, determining a number of subscriber devices that have selected to record the multi-media content. At the particular broadcast time, the method continues with the processing module receiving the multi-media content as it is being broadcast. When the number of subscriber devices is less than a first value, the method continues with the processing module encoding the multi-media content using first level encoding parameters to produce sets of first level encoded data slices for storage. When the number of subscriber devices is equal to or greater than the first value, the method continues with the processing module encoding the multi-media content using second level encoding parameters to produce sets of second level encoded data slices for storage.

CROSS REFERENCE TO RELATED PATENTS

The present U.S. Utility patent application claims priority pursuant to35 U.S.C. §120 as a continuation-in-part of U.S. Utility applicationSer. No. 12/903,212, entitled “DIGITAL CONTENT RETRIEVAL UTILIZINGDISPERSED STORAGE,” filed Oct. 13, 2010, pending, which claims prioritypursuant to 35 U.S.C. §119(e) to U.S. Provisional Application No.61/290,632, entitled “DIGITAL CONTENT DISTRIBUTED STORAGE,” filed Dec.29, 2009, all of which are hereby incorporated herein by reference intheir entirety and made part of the present U.S. Utility patentapplication for all purposes.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not Applicable

INCORPORATION-BY-REFERENCE OF MATERIAL SUBMITTED ON A COMPACT DISC

Not Applicable

BACKGROUND OF THE INVENTION

1. Technical Field of the Invention

This invention relates generally to computing systems and moreparticularly to data storage solutions within such computing systems.

2. Description of Related Art

Computers are known to communicate, process, and store data. Suchcomputers range from wireless smart phones to data centers that supportmillions of web searches, stock trades, or on-line purchases every day.In general, a computing system generates data and/or manipulates datafrom one form into another. For instance, an image sensor of thecomputing system generates raw picture data and, using an imagecompression program (e.g., JPEG, MPEG, etc.), the computing systemmanipulates the raw picture data into a standardized compressed image.

With continued advances in processing speed and communication speed,computers are capable of processing real time multimedia data forapplications ranging from simple voice communications to streaming highdefinition video. As such, general-purpose information appliances arereplacing purpose-built communications devices (e.g., a telephone). Forexample, smart phones can support telephony communications but they arealso capable of text messaging and accessing the internet to performfunctions including email, web browsing, remote applications access, andmedia communications (e.g., telephony voice, image transfer, musicfiles, video files, real time video streaming. etc.).

Each type of computer is constructed and operates in accordance with oneor more communication, processing, and storage standards. As a result ofstandardization and with advances in technology, more and moreinformation content is being converted into digital formats. Forexample, more digital cameras are now being sold than film cameras, thusproducing more digital pictures. As another example, web-basedprogramming is becoming an alternative to over the air televisionbroadcasts and/or cable broadcasts. As further examples, papers, books,video entertainment, home video, etc., are now being stored digitally,which increases the demand on the storage function of computers.

A typical computer storage system includes one or more memory devicesaligned with the needs of the various operational aspects of thecomputer's processing and communication functions. Generally, theimmediacy of access dictates what type of memory device is used. Forexample, random access memory (RAM) memory can be accessed in any randomorder with a constant response time, thus it is typically used for cachememory and main memory. By contrast, memory device technologies thatrequire physical movement such as magnetic disks, tapes, and opticaldiscs, have a variable response time as the physical movement can takelonger than the data transfer, thus they are typically used forsecondary memory (e.g., hard drive, backup memory, etc.).

A computer's storage system will be compliant with one or more computerstorage standards that include, but are not limited to, network filesystem (NFS), flash file system (FFS), disk file system (DFS), smallcomputer system interface (SCSI), internet small computer systeminterface (iSCSI), file transfer protocol (FTP), and web-baseddistributed authoring and versioning (WebDAV). These standards specifythe data storage format (e.g., files, data objects, data blocks,directories, etc.) and interfacing between the computer's processingfunction and its storage system, which is a primary function of thecomputer's memory controller.

Despite the standardization of the computer and its storage system,memory devices fail; especially commercial grade memory devices thatutilize technologies incorporating physical movement (e.g., a discdrive). For example, it is fairly common for a disc drive to routinelysuffer from bit level corruption and to completely fail after threeyears of use. One solution is to utilize a higher-grade disc drive,which adds significant cost to a computer.

Another solution is to utilize multiple levels of redundant disc drivesto replicate the data into two or more copies. One such redundant driveapproach is called redundant array of independent discs (RAID). In aRAID device, a RAID controller adds parity data to the original databefore storing it across the array. The parity data is calculated fromthe original data such that the failure of a disc will not result in theloss of the original data. For example, RAID 5 uses three discs toprotect data from the failure of a single disc. The parity data, andassociated redundancy overhead data, reduces the storage capacity ofthree independent discs by one third (e.g., n−1=capacity). RAID 6 canrecover from a loss of two discs and requires a minimum of four discswith a storage capacity of n−2.

While RAID addresses the memory device failure issue, it is not withoutits own failure issues that affect its effectiveness, efficiency andsecurity. For instance, as more discs are added to the array, theprobability of a disc failure increases, which increases the demand formaintenance. For example, when a disc fails, it needs to be manuallyreplaced before another disc fails and the data stored in the RAIDdevice is lost. To reduce the risk of data loss, data on a RAID deviceis typically copied on to one or more other RAID devices. While thisaddresses the loss of data issue, it raises a security issue sincemultiple copies of data are available, which increases the chances ofunauthorized access. Further, as the amount of data being stored grows,the overhead of RAID devices becomes a non-trivial efficiency issue.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)

FIG. 1 is a schematic block diagram of an embodiment of a computingsystem in accordance with the present invention;

FIG. 2 is a schematic block diagram of an embodiment of a computing corein accordance with the present invention;

FIG. 3 is a schematic block diagram of an embodiment of a distributedstorage processing unit in accordance with the present invention;

FIG. 4 is a schematic block diagram of an embodiment of a grid module inaccordance with the present invention;

FIG. 5 is a diagram of an example embodiment of error coded data slicecreation in accordance with the present invention;

FIG. 6 is a schematic block diagram of another embodiment of a computingsystem in accordance with the present invention;

FIG. 7 is a flowchart illustrating an example of storing content inaccordance with the present invention;

FIG. 8A is a flowchart illustrating an example of retrieving content inaccordance with the present invention;

FIG. 8B is a flowchart illustrating another example of retrievingcontent in accordance with the present invention;

FIG. 9 is a schematic block diagram of another embodiment of a computingsystem in accordance with the present invention;

FIG. 10 is a schematic block diagram of another embodiment of acomputing system in accordance with the present invention;

FIG. 11 is an illustration of an example content ingestion table inaccordance with the present invention;

FIG. 12 is an illustration of an example user access rights table inaccordance with the present invention;

FIG. 13 is a flowchart illustrating another example of retrievingcontent in accordance with the present invention;

FIG. 14 is a flowchart illustrating an example of determining useraccess rights in accordance with the present invention;

FIG. 15 is a flowchart illustrating another example of determining useraccess rights in accordance with the present invention;

FIG. 16 is a flowchart illustrating an example of modifying user accessrights in accordance with the present invention;

FIG. 17A is a schematic block diagram of another embodiment of acomputing system in accordance with the present invention;

FIG. 17B is a flowchart illustrating another example of retrievingcontent in accordance with the present invention;

FIG. 18A is a flowchart illustrating another example of retrievingcontent in accordance with the present invention;

FIG. 18B is a flowchart illustrating another example of retrievingcontent in accordance with the present invention; and

FIG. 19 is a flowchart illustrating another example of retrievingcontent in accordance with the present invention.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 is a schematic block diagram of a computing system 10 thatincludes one or more of a first type of user devices 12, one or more ofa second type of user devices 14, at least one distributed storage (DS)processing unit 16, at least one DS managing unit 18, at least onestorage integrity processing unit 20, and a distributed storage network(DSN) memory 22 coupled via a network 24. The network 24 may include oneor more wireless and/or wire lined communication systems; one or moreprivate intranet systems and/or public internet systems; and/or one ormore local area networks (LAN) and/or wide area networks (WAN).

The DSN memory 22 includes a plurality of distributed storage (DS) units36 for storing data of the system. Each of the DS units 36 includes aprocessing module and memory and may be located at a geographicallydifferent site than the other DS units (e.g., one in Chicago, one inMilwaukee, etc.). The processing module may be a single processingdevice or a plurality of processing devices. Such a processing devicemay be a microprocessor, micro-controller, digital signal processor,microcomputer, central processing unit, field programmable gate array,programmable logic device, state machine, logic circuitry, analogcircuitry, digital circuitry, and/or any device that manipulates signals(analog and/or digital) based on hard coding of the circuitry and/oroperational instructions. The processing module may have an associatedmemory and/or memory element, which may be a single memory device, aplurality of memory devices, and/or embedded circuitry of the processingmodule. Such a memory device may be a read-only memory, random accessmemory, volatile memory, non-volatile memory, static memory, dynamicmemory, flash memory, cache memory, and/or any device that storesdigital information. Note that if the processing module includes morethan one processing device, the processing devices may be centrallylocated (e.g., directly coupled together via a wired and/or wireless busstructure) or may be distributedly located (e.g., cloud computing viaindirect coupling via a local area network and/or a wide area network).Further note that when the processing module implements one or more ofits functions via a state machine, analog circuitry, digital circuitry,and/or logic circuitry, the memory and/or memory element storing thecorresponding operational instructions may be embedded within, orexternal to, the circuitry comprising the state machine, analogcircuitry, digital circuitry, and/or logic circuitry. Still further notethat, the memory element stores, and the processing module executes,hard coded and/or operational instructions corresponding to at leastsome of the steps and/or functions illustrated in FIGS. 1-19.

Each of the user devices 12-14, the DS processing unit 16, the DSmanaging unit 18, and the storage integrity processing unit 20 may be aportable computing device (e.g., a social networking device, a gamingdevice, a cell phone, a smart phone, a personal digital assistant, adigital music player, a digital video player, a laptop computer, ahandheld computer, a video game controller, and/or any other portabledevice that includes a computing core) and/or a fixed computing device(e.g., a personal computer, a computer server, a cable set-top box, asatellite receiver, a television set, a printer, a fax machine, homeentertainment equipment, a video game console, and/or any type of homeor office computing equipment). Such a portable or fixed computingdevice includes a computing core 26 and one or more interfaces 30, 32,and/or 33. An embodiment of the computing core 26 will be described withreference to FIG. 2.

With respect to the interfaces, each of the interfaces 30, 32, and 33includes software and/or hardware to support one or more communicationlinks via the network 24 and/or directly. For example, interface 30supports a communication link (wired, wireless, direct, via a LAN, viathe network 24, etc.) between the first type of user device 14 and theDS processing unit 16. As another example, DSN interface 32 supports aplurality of communication links via the network 24 between the DSNmemory 22 and the DS processing unit 16, the first type of user device12, and/or the storage integrity processing unit 20. As yet anotherexample, interface 33 supports a communication link between the DSmanaging unit 18 and any one of the other devices and/or units 12, 14,16, 20, and/or 22 via the network 24.

In general and with respect to data storage, the system 10 supportsthree primary functions: distributed network data storage management,distributed data storage and retrieval, and data storage integrityverification. In accordance with these three primary functions, data canbe distributedly stored in a plurality of physically different locationsand subsequently retrieved in a reliable and secure manner regardless offailures of individual storage devices (e.g., storage units), failuresof network equipment, the duration of storage, the amount of data beingstored, attempts at hacking the data, etc.

The DS managing unit 18 performs distributed network data storagemanagement functions, which include establishing distributed datastorage parameters, performing network operations, performing networkadministration, and/or performing network maintenance. The DS managingunit 18 establishes the distributed data storage parameters (e.g.,allocation of virtual DSN memory space, distributed storage parameters,security parameters, billing information, user profile information,etc.) for one or more of the user devices 12-14 (e.g., established forindividual devices, established for a user group of devices, establishedfor public access by the user devices, etc.). For example, the DSmanaging unit 18 coordinates the creation of a vault (e.g., a virtualmemory block) within the DSN memory 22 for a user device (for a group ofdevices, or for public access). The DS managing unit 18 also determinesthe distributed data storage parameters for the vault. In particular,the DS managing unit 18 determines a number of slices (e.g., the numberthat a data segment of a data file and/or data block is partitioned intofor distributed storage) and a read threshold value (e.g., the minimumnumber of slices required to reconstruct the data segment).

As another example, the DS managing unit 18 creates and stores, locallyor within the DSN memory 22, user profile information. The user profileinformation includes one or more of authentication information,permissions, and/or the security parameters. The security parameters mayinclude one or more of encryption/decryption scheme, one or moreencryption keys, key generation scheme, and data encoding/decodingscheme.

As yet another example, the DS managing unit 18 creates billinginformation for a particular user, user group, vault access, publicvault access, etc. For instance, the DS managing unit 18 tracks thenumber of times a user accesses a private vault and/or public vaults,which can be used to generate a per-access bill. In another instance,the DS managing unit 18 tracks the amount of data stored and/orretrieved by a user device and/or a user group, which can be used togenerate a per-data-amount bill.

The DS managing unit 18 also performs network operations, networkadministration, and/or network maintenance. As at least part ofperforming the network operations and/or administration, the DS managingunit 18 monitors performance of the devices and/or units of the system10 for potential failures, determines the devices' and/or units'activation status, determines the devices' and/or units' loading, andany other system level operation that affects the performance level ofthe system 10. For example, the DS managing unit 18 receives andaggregates network management alarms, alerts, errors, statusinformation, performance information, and messages from the devices12-14 and/or the units 16, 20, 22. For example, the DS managing unit 18receives a simple network management protocol (SNMP) message regardingthe status of the DS processing unit 16.

The DS managing unit 18 performs the network maintenance by identifyingequipment within the system 10 that needs replacing, upgrading,repairing, and/or expanding. For example, the DS managing unit 18determines that the DSN memory 22 needs more DS units 36 or that one ormore of the DS units 36 needs updating.

The second primary function (i.e., distributed data storage andretrieval) begins and ends with a user device 12-14. For instance, if asecond type of user device 14 has a data file 38 and/or data block 40 tostore in the DSN memory 22, it sends the data file 38 and/or data block40 to the DS processing unit 16 via its interface 30. As will bedescribed in greater detail with reference to FIG. 2, the interface 30functions to mimic a conventional operating system (OS) file systeminterface (e.g., network file system (NFS), flash file system (FFS),disk file system (DFS), file transfer protocol (FTP), web-baseddistributed authoring and versioning (WebDAV), etc.) and/or a blockmemory interface (e.g., small computer system interface (SCSI), internetsmall computer system interface (iSCSI), etc.). In addition, theinterface 30 may attach a user identification code (ID) to the data file38 and/or data block 40.

The DS processing unit 16 receives the data file 38 and/or data block 40via its interface 30 and performs a distributed storage (DS) process 34thereon (e.g., an error coding dispersal storage function). The DSprocessing 34 begins by partitioning the data file 38 and/or data block40 into one or more data segments, which is represented as Y datasegments. For example, the DS processing 34 may partition the data file38 and/or data block 40 into a fixed byte size segment (e.g., 2¹ to2^(n) bytes, where n=>2) or a variable byte size (e.g., change byte sizefrom segment to segment, or from groups of segments to groups ofsegments, etc.).

For each of the Y data segments, the DS processing 34 error encodes(e.g., forward error correction (FEC), information dispersal algorithm,or error correction coding) and slices (or slices then error encodes)the data segment into a plurality of error coded (EC) data slices 42-48,which is represented as X slices per data segment. The number of slices(X) per segment, which corresponds to a number of pillars n, is set inaccordance with the distributed data storage parameters and the errorcoding scheme. For example, if a Reed-Solomon (or other FEC scheme) isused in an n/k system, then a data segment is divided into n slices,where k number of slices is needed to reconstruct the original data(i.e., k is the threshold). As a few specific examples, the n/k factormay be 5/3; 6/4; 8/6; 8/5; 16/10.

For each EC slice 42-48, the DS processing unit 16 creates a uniqueslice name and appends it to the corresponding EC slice 42-48. The slicename includes universal DSN memory addressing routing information (e.g.,virtual memory addresses in the DSN memory 22) and user-specificinformation (e.g., user ID, file name, data block identifier, etc.).

The DS processing unit 16 transmits the plurality of EC slices 42-48 toa plurality of DS units 36 of the DSN memory 22 via the DSN interface 32and the network 24. The DSN interface 32 formats each of the slices fortransmission via the network 24. For example, the DSN interface 32 mayutilize an internet protocol (e.g., TCP/IP, etc.) to packetize the ECslices 42-48 for transmission via the network 24.

The number of DS units 36 receiving the EC slices 42-48 is dependent onthe distributed data storage parameters established by the DS managingunit 18. For example, the DS managing unit 18 may indicate that eachslice is to be stored in a different DS unit 36. As another example, theDS managing unit 18 may indicate that like slice numbers of differentdata segments are to be stored in the same DS unit 36. For example, thefirst slice of each of the data segments is to be stored in a first DSunit 36, the second slice of each of the data segments is to be storedin a second DS unit 36, etc. In this manner, the data is encoded anddistributedly stored at physically diverse locations to improve datastorage integrity and security. Further examples of encoding the datasegments will be provided with reference to one or more of FIGS. 2-19.

Each DS unit 36 that receives an EC slice 42-48 for storage translatesthe virtual DSN memory address of the slice into a local physicaladdress for storage. Accordingly, each DS unit 36 maintains a virtual tophysical memory mapping to assist in the storage and retrieval of data.

The first type of user device 12 performs a similar function to storedata in the DSN memory 22 with the exception that it includes the DSprocessing. As such, the device 12 encodes and slices the data fileand/or data block it has to store. The device then transmits the slices11 to the DSN memory via its DSN interface 32 and the network 24.

For a second type of user device 14 to retrieve a data file or datablock from memory, it issues a read command via its interface 30 to theDS processing unit 16. The DS processing unit 16 performs the DSprocessing 34 to identify the DS units 36 storing the slices of the datafile and/or data block based on the read command. The DS processing unit16 may also communicate with the DS managing unit 18 to verify that theuser device 14 is authorized to access the requested data.

Assuming that the user device is authorized to access the requesteddata, the DS processing unit 16 issues slice read commands to at least athreshold number of the DS units 36 storing the requested data (e.g., toat least 10 DS units for a 16/10 error coding scheme). Each of the DSunits 36 receiving the slice read command, verifies the command,accesses its virtual to physical memory mapping, retrieves the requestedslice, or slices, and transmits it to the DS processing unit 16.

Once the DS processing unit 16 has received a read threshold number ofslices for a data segment, it performs an error decoding function andde-slicing to reconstruct the data segment. When Y number of datasegments has been reconstructed, the DS processing unit 16 provides thedata file 38 and/or data block 40 to the user device 14. Note that thefirst type of user device 12 performs a similar process to retrieve adata file and/or data block.

The storage integrity processing unit 20 performs the third primaryfunction of data storage integrity verification. In general, the storageintegrity processing unit 20 periodically retrieves slices 45, and/orslice names, of a data file or data block of a user device to verifythat one or more slices have not been corrupted or lost (e.g., the DSunit failed). The retrieval process mimics the read process previouslydescribed.

If the storage integrity processing unit 20 determines that one or moreslices is corrupted or lost, it rebuilds the corrupted or lost slice(s)in accordance with the error coding scheme. The storage integrityprocessing unit 20 stores the rebuilt slice, or slices, in theappropriate DS unit(s) 36 in a manner that mimics the write processpreviously described.

FIG. 2 is a schematic block diagram of an embodiment of a computing core26 that includes a processing module 50, a memory controller 52, mainmemory 54, a video graphics processing unit 55, an input/output (IO)controller 56, a peripheral component interconnect (PCI) interface 58,an IO interface 60, at least one IO device interface module 62, a readonly memory (ROM) basic input output system (BIOS) 64, and one or morememory interface modules. The memory interface module(s) includes one ormore of a universal serial bus (USB) interface module 66, a host busadapter (HBA) interface module 68, a network interface module 70, aflash interface module 72, a hard drive interface module 74, and a DSNinterface module 76. Note the DSN interface module 76 and/or the networkinterface module 70 may function as the interface 30 of the user device14 of FIG. 1. Further note that the IO device interface module 62 and/orthe memory interface modules may be collectively or individuallyreferred to as IO ports.

The processing module 50 may be a single processing device or aplurality of processing devices. Such a processing device may be amicroprocessor, micro-controller, digital signal processor,microcomputer, central processing unit, field programmable gate array,programmable logic device, state machine, logic circuitry, analogcircuitry, digital circuitry, and/or any device that manipulates signals(analog and/or digital) based on hard coding of the circuitry and/oroperational instructions. The processing module 50 may have anassociated memory and/or memory element, which may be a single memorydevice, a plurality of memory devices, and/or embedded circuitry of theprocessing module 50. Such a memory device may be a read-only memory,random access memory, volatile memory, non-volatile memory, staticmemory, dynamic memory, flash memory, cache memory, and/or any devicethat stores digital information. Note that if the processing module 50includes more than one processing device, the processing devices may becentrally located (e.g., directly coupled together via a wired and/orwireless bus structure) or may be distributedly located (e.g., cloudcomputing via indirect coupling via a local area network and/or a widearea network). Further note that when the processing module 50implements one or more of its functions via a state machine, analogcircuitry, digital circuitry, and/or logic circuitry, the memory and/ormemory element storing the corresponding operational instructions may beembedded within, or external to, the circuitry comprising the statemachine, analog circuitry, digital circuitry, and/or logic circuitry.Still further note that, the memory element stores, and the processingmodule 50 executes, hard coded and/or operational instructionscorresponding to at least some of the steps and/or functions illustratedin FIGS. 1-19.

FIG. 3 is a schematic block diagram of an embodiment of a dispersedstorage (DS) processing module 34 of user device 12 and/or of the DSprocessing unit 16. The DS processing module 34 includes a gatewaymodule 78, an access module 80, a grid module 82, and a storage module84. The DS processing module 34 may also include an interface 30 and theDSnet interface 32 or the interfaces 68 and/or 70 and may be part ofuser device 12 or of the DS processing unit 16. The DS processing module34 may further include a bypass/feedback path between the storage module84 to the gateway module 78. Note that the modules 78-84 of the DSprocessing module 34 may be in a single unit or distributed acrossmultiple units.

In an example of storing data, the gateway module 78 receives anincoming data object that includes a user ID field 86, an object namefield 88, and the data object field 40 and may also receivecorresponding information that includes a process identifier (e.g., aninternal process/application ID), metadata, a file system directory, ablock number, a transaction message, a user device identity (ID), a dataobject identifier, a source name, and/or user information. The gatewaymodule 78 authenticates the user associated with the data object byverifying the user ID 86 with the DS managing unit 18 and/or anotherauthenticating unit.

When the user is authenticated, the gateway module 78 obtains userinformation from the management unit 18, the user device, and/or theother authenticating unit. The user information includes a vaultidentifier, operational parameters, and user attributes (e.g., userdata, billing information, etc.). A vault identifier identifies a vault,which is a virtual memory space that maps to a set of DS storage units36. For example, vault 1 (i.e., user 1's DSN memory space) includeseight DS storage units (X=8 wide) and vault 2 (i.e., user 2's DSN memoryspace) includes sixteen DS storage units (X=16 wide). The operationalparameters may include an error coding algorithm, the width n (number ofpillars X or slices per segment for this vault), a read threshold T, awrite threshold, an encryption algorithm, a slicing parameter, acompression algorithm, an integrity check method, caching settings,parallelism settings, and/or other parameters that may be used to accessthe DSN memory layer.

The gateway module 78 uses the user information to assign a source name35 to the data. For instance, the gateway module 78 determines thesource name 35 of the data object 40 based on the vault identifier andthe data object. For example, the source name may contain a fileidentifier (ID), a vault generation number, a reserved field, and avault identifier (ID). As another example, the gateway module 78 maygenerate the file ID based on a hash function of the data object 40.Note that the gateway module 78 may also perform message conversion,protocol conversion, electrical conversion, optical conversion, accesscontrol, user identification, user information retrieval, trafficmonitoring, statistics generation, configuration, management, and/orsource name determination.

The access module 80 receives the data object 40 and creates a series ofdata segments 1 through Y 90-92 in accordance with a data storageprotocol (e.g., file storage system, a block storage system, and/or anaggregated block storage system). The number of segments Y may be chosenor randomly assigned based on a selected segment size and the size ofthe data object. For example, if the number of segments is chosen to bea fixed number, then the size of the segments varies as a function ofthe size of the data object. For instance, if the data object is animage file of 4,194,304 eight bit bytes (e.g., 33,554,432 bits) and thenumber of segments Y=131,072, then each segment is 256 bits or 32 bytes.As another example, if segment size is fixed, then the number ofsegments Y varies based on the size of data object. For instance, if thedata object is an image file of 4,194,304 bytes and the fixed size ofeach segment is 4,096 bytes, the then number of segments Y=1,024. Notethat each segment is associated with the same source name.

The grid module 82 receives the data segments and may manipulate (e.g.,compression, encryption, cyclic redundancy check (CRC), etc.) each ofthe data segments before performing an error coding function of theerror coding dispersal storage function to produce a pre-manipulateddata segment. After manipulating a data segment, if applicable, the gridmodule 82 error encodes (e.g., Reed-Solomon, Convolution encoding,Trellis encoding, etc.) the data segment or manipulated data segmentinto X error coded data slices 42-44.

The value X, or the number of pillars (e.g., X=16), is chosen as aparameter of the error coding dispersal storage function. Otherparameters of the error coding dispersal function include a readthreshold T, a write threshold W, etc. The read threshold (e.g., T=10,when X=16) corresponds to the minimum number of error-free error codeddata slices required to reconstruct the data segment. In other words,the DS processing module 34 can compensate for X-T (e.g., 16−10=6)missing error coded data slices per data segment. The write threshold Wcorresponds to a minimum number of DS storage units that acknowledgeproper storage of their respective data slices before the DS processingmodule indicates proper storage of the encoded data segment. Note thatthe write threshold is greater than or equal to the read threshold for agiven number of pillars (X).

For each data slice of a data segment, the grid module 82 generates aunique slice name 37 and attaches it thereto. The slice name 37 includesa universal routing information field and a vault specific field and maybe 48 bytes (e.g., 24 bytes for each of the universal routinginformation field and the vault specific field). As illustrated, theuniversal routing information field includes a slice index, a vault ID,a vault generation, and a reserved field. The slice index is based onthe pillar number and the vault ID and, as such, is unique for eachpillar (e.g., slices of the same pillar for the same vault for anysegment will share the same slice index). The vault specific fieldincludes a data name, which includes a file ID and a segment number(e.g., a sequential numbering of data segments 1-Y of a simple dataobject or a data block number).

Prior to outputting the error coded data slices of a data segment, thegrid module may perform post-slice manipulation on the slices. Ifenabled, the manipulation includes slice level compression, encryption,CRC, addressing, tagging, and/or other manipulation to improve theeffectiveness of the computing system.

When the error coded data slices of a data segment are ready to beoutputted, the grid module 82 determines which of the DS storage units36 will store the EC data slices based on a dispersed storage memorymapping associated with the user's vault and/or DS storage unitattributes. The DS storage unit attributes may include availability,self-selection, performance history, link speed, link latency,ownership, available DSN memory, domain, cost, a prioritization scheme,a centralized selection message from another source, a lookup table,data ownership, and/or any other factor to optimize the operation of thecomputing system. Note that the number of DS storage units 36 is equalto or greater than the number of pillars (e.g., X) so that no more thanone error coded data slice of the same data segment is stored on thesame DS storage unit 36. Further note that EC data slices of the samepillar number but of different segments (e.g., EC data slice 1 of datasegment 1 and EC data slice 1 of data segment 2) may be stored on thesame or different DS storage units 36.

The storage module 84 performs an integrity check on the outboundencoded data slices and, when successful, identifies a plurality of DSstorage units based on information provided by the grid module 82. Thestorage module 84 then outputs the encoded data slices 1 through X ofeach segment 1 through Y to the DS storage units 36. Each of the DSstorage units 36 stores its EC data slice(s) and maintains a localvirtual DSN address to physical location table to convert the virtualDSN address of the EC data slice(s) into physical storage addresses.

In an example of a read operation, the user device 12 and/or 14 sends aread request to the DS processing unit 16, which authenticates therequest. When the request is authentic, the DS processing unit 16 sendsa read message to each of the DS storage units 36 storing slices of thedata object being read. The slices are received via the DSnet interface32 and processed by the storage module 84, which performs a parity checkand provides the slices to the grid module 82 when the parity check wassuccessful. The grid module 82 decodes the slices in accordance with theerror coding dispersal storage function to reconstruct the data segment.The access module 80 reconstructs the data object from the data segmentsand the gateway module 78 formats the data object for transmission tothe user device.

FIG. 4 is a schematic block diagram of an embodiment of a grid module 82that includes a control unit 73, a pre-slice manipulator 75, an encoder77, a slicer 79, a post-slice manipulator 81, a pre-slice de-manipulator83, a decoder 85, a de-slicer 87, and/or a post-slice de-manipulator 89.Note that the control unit 73 may be partially or completely external tothe grid module 82. For example, the control unit 73 may be part of thecomputing core at a remote location, part of a user device, part of theDS managing unit 18, or distributed amongst one or more DS storageunits.

In an example of a write operation, the pre-slice manipulator 75receives a data segment 90-92 and a write instruction from an authorizeduser device. The pre-slice manipulator 75 determines if pre-manipulationof the data segment 90-92 is required and, if so, what type. Thepre-slice manipulator 75 may make the determination independently orbased on instructions from the control unit 73, where the determinationis based on a computing system-wide predetermination, a table lookup,vault parameters associated with the user identification, the type ofdata, security requirements, available DSN memory, performancerequirements, and/or other metadata.

Once a positive determination is made, the pre-slice manipulator 75manipulates the data segment 90-92 in accordance with the type ofmanipulation. For example, the type of manipulation may be compression(e.g., Lempel-Ziv-Welch, Huffman, Golomb, fractal, wavelet, etc.),signatures (e.g., Digital Signature Algorithm (DSA), Elliptic Curve DSA,Secure Hash Algorithm, etc.), watermarking, tagging, encryption (e.g.,Data Encryption Standard, Advanced Encryption Standard, etc.), addingmetadata (e.g., time/date stamping, user information, file type, etc.),cyclic redundancy check (e.g., CRC32), and/or other data manipulationsto produce the pre-manipulated data segment.

The encoder 77 encodes the pre-manipulated data segment 92 using aforward error correction (FEC) encoder (and/or other type of erasurecoding and/or error coding) to produce an encoded data segment 94. Theencoder 77 determines which forward error correction algorithm to usebased on a predetermination associated with the user's vault, a timebased algorithm, user direction, DS managing unit direction, controlunit direction, as a function of the data type, as a function of thedata segment 92 metadata, and/or any other factor to determine algorithmtype. The forward error correction algorithm may be Golay,Multidimensional parity, Reed-Solomon, Hamming, Bose Ray ChauduriHocquenghem (BCH), Cauchy-Reed-Solomon, or any other FEC encoder. Notethat the encoder 77 may use a different encoding algorithm for each datasegment 92, the same encoding algorithm for the data segments 92 of adata object, or a combination thereof.

The encoded data segment 94 is of greater size than the data segment 92by the overhead rate of the encoding algorithm by a factor of X/T, whereX is the width or number of slices, and T is the read threshold. In thisregard, the corresponding decoding process can accommodate at most X-Tmissing EC data slices and still recreate the data segment 92. Forexample, if X=16 and T=10, then the data segment 92 will be recoverableas long as 10 or more EC data slices per segment are not corrupted.

The slicer 79 transforms the encoded data segment 94 into EC data slicesin accordance with the slicing parameter from the vault for this userand/or data segment 92. For example, if the slicing parameter is X=16,then the slicer 79 slices each encoded data segment 94 into 16 encodedslices.

The post-slice manipulator 81 performs, if enabled, post-manipulation onthe encoded slices to produce the EC data slices. If enabled, thepost-slice manipulator 81 determines the type of post-manipulation,which may be based on a computing system-wide predetermination,parameters in the vault for this user, a table lookup, the useridentification, the type of data, security requirements, available DSNmemory, performance requirements, control unit directed, and/or othermetadata. Note that the type of post-slice manipulation may includeslice level compression, signatures, encryption, CRC, addressing,watermarking, tagging, adding metadata, and/or other manipulation toimprove the effectiveness of the computing system.

In an example of a read operation, the post-slice de-manipulator 89receives at least a read threshold number of EC data slices and performsthe inverse function of the post-slice manipulator 81 to produce aplurality of encoded slices. The de-slicer 87 de-slices the encodedslices to produce an encoded data segment 94. The decoder 85 performsthe inverse function of the encoder 77 to recapture the data segment90-92. The pre-slice de-manipulator 83 performs the inverse function ofthe pre-slice manipulator 75 to recapture the data segment 90-92.

FIG. 5 is a diagram of an example of slicing an encoded data segment 94by the slicer 79. In this example, the encoded data segment 94 includesthirty-two bits, but may include more or less bits. The slicer 79disperses the bits of the encoded data segment 94 across the EC dataslices in a pattern as shown. As such, each EC data slice does notinclude consecutive bits of the data segment 94 reducing the impact ofconsecutive bit failures on data recovery. For example, if EC data slice2 (which includes bits 1, 5, 9, 13, 17, 25, and 29) is unavailable(e.g., lost, inaccessible, or corrupted), the data segment can bereconstructed from the other EC data slices (e.g., 1, 3 and 4 for a readthreshold of 3 and a width of 4).

FIG. 6 is another schematic block diagram of another embodiment of acomputing system. As illustrated, the system includes at least oneingest dispersed storage (DS) processing unit 102, a dispersed storagenetwork (DSN) memory 22, a retrieval DS processing unit 104, adistribution network 106, a plurality of set top boxes 1-V, and aplurality of viewers 1-V. The DSN memory 22 includes a plurality ofdispersed storage (DS) units 1-n as previously discussed. Alternatively,the DSN memory 22 is implemented in one or more of the set top boxes1-V. The ingest DS processing unit 102 and the retrieval DS processingunit 104 functions include those discussed previously with reference tothe DS processing unit 16 (e.g., of FIGS. 1-5) and additionalfunctionality as discussed with reference to one or more of FIGS. 6-19.Alternatively, the ingest DS processing unit 102 and the retrieval DSprocessing unit 104 are implemented in the same DS unit 16.Alternatively, the ingest DS processing unit 102 and the retrieval DSprocessing unit 104 are implemented in at least one of set top boxes1-V. Note that the ingest DS processing unit 102 may be operably coupledto the retrieval DS processing unit 104 to facilitate exchangesincluding commands and content. The distribution network 106 may beimplemented utilizing one or more of a hybrid fiber coax system, asatellite system, an internet access system, and a wireless system.

The set top boxes 1-V include the computing core 26 of FIG. 2 and a DSprocessing 34. The set top boxes 1-V reproduce broadcast data in aformat compatible with the viewers 1-V. The viewers 1-V may include adisplay and speakers such as a flat panel television to reproducebroadcast data. As illustrated, the plurality of set top boxes 1-V isoperably coupled via the distribution network 106 to the retrieval DSprocessing unit 104. Alternatively, or in addition to, the set top boxes1-V are operably coupled directly to the DS units 1-n and/or directly tothe ingest DS processing unit 102. Alternatively, the functions of theset top boxes 1-V and viewer 1-V are integrated together. In an example,viewer 3 (e.g., including set top box 3 functionality) may be operablycoupled to the retrieval DS processing unit 104 and to the DSN memory22.

In an example of operation, the ingest DS processing 102 receivescontent 108 (e.g., broadcast data, cable television programming,internet media feeds, broadcast satellite feeds, etc.). Note thatbroadcast data may include one or more portions (e.g., TV programs) ofcontent 108. A method of operation of a processing module (e.g., of theingest DS processing 102) begins with the step where the processingmodule determines whether to error encode broadcast data. Such adetermination may be based on at least one of detecting new broadcastdata content (e.g., not already stored in the DSN memory 22), apredetermined schedule (e.g., a recording schedule based on inputs fromat least one set top box or from a system operator schedule), abroadcast data request message (e.g., from at least one set top box).For example, the processing module determines to error encode thebroadcast data when the process module determines that the broadcastdata is not already been stored in the DSN memory 22. In anotherexample, the processing module determines to error encode the broadcastdata when at least one set top box has previously requested thebroadcast data. The processing module ignores the broadcast data whenthe processing module determines not to error encode the broadcast data.The method continues to the next step when the processing moduledetermines to error encode the broadcast data.

In the next step, the processing module encodes a portion of thebroadcast data using an error coding dispersal storage function toproduce a set of encoded broadcast data slices. Next, the processingmodule determines whether to compress the set of encoded broadcast dataslices. Such a determination may be based on one or more of a minimumrequired slice pillar indicator, a slicing pillar width, a reliabilityrequirement, an availability requirement, a distribution networkreliability indicator, a message, a look up, and a command. In anexample, the processing module determines to compress the set of encodedbroadcast data slices when the process module determines that theminimum required slice pillar indicator is less than the slicing pillarwidth. Note that the minimum required slice pillar indicator representsparticular slice pillars that are required or preferred to subsequentlydecode the encoded broadcast data slices to reproduce the broadcastdata. For instance, the minimum required slice pillar indicator listspillars 1-12 when the pillar width is 16. As such, pillars 13-16 are notmandated and may not be included in a subsequent subset selection ofslice pillars. The method branches to the step where the processingmodule selects a subset of encoded broadcast data slices when theprocessing module determines to compress the set of encoded broadcastdata slices. The method continues to the next step when the processingmodule determines not to compress the set of encoded broadcast dataslices. In the next step, during a live broadcast of the broadcast data,the processing module sends the set of encoded broadcast data slices(e.g., as broadcast slices to set top boxes 1-V when the ingest DSprocessing unit 102 is operably coupled to the set top boxes 1-V) whenthe set of encoded broadcast data slices was not compressed.

The processing module selects a subset of encoded broadcast data slicesof the set of encoded broadcast data slices when the set of encodedbroadcast data slices is to be compressed. Such a selection may be basedon one or more of the minimum required slice pillar indicator, theslicing pillar width, a reliability requirement, an availabilityrequirement, the distribution network reliability indicator, a message,a look up, and a command. In example, the processing module selectspillars 1-12 as the subset of encoded broadcast data slices when theminimum required slice pillar indicator lists pillars 1-12. Next, duringa live broadcast of the broadcast data, the processing module sends thesubset of encoded broadcast data slices (e.g., as broadcast slices toset top boxes 1-V when the ingest DS processing unit 102 is operablycoupled to the set top boxes 1-V) when the set of encoded broadcast dataslices was compressed.

The example of operation continues with the step where the processingmodule sends the set of encoded broadcast data slices (e.g., asillustrated: pillar 1 slices, pillar 2 slices, through pillar n slices)to the DSN memory 22 for storage therein. Alternatively, the processingmodule sends the set of encoded broadcast data slices to the DSN memory22 in response to receiving at least one retrieval request 110 from atleast one of the set top boxes 1-V.

Note that the set top boxes 1-V may receive live broadcast slices fromthe ingest DS processing unit 102 when the set top boxes 1-V areoperably coupled to the ingest DS processing unit 102. Alternatively, orin addition to, the set top boxes 1-V send retrieval requests 110 to theDSN memory 22 or to the retrieval DS processing unit 104 and receiveretrieved slices 112 in response thus facilitating a playback ofbroadcast data. In an example of operation, during a playback of thebroadcast data by set top box 4, the processing module receives aretrieval request 110 from a playback device (e.g., set top box 4).Next, the processing module determines a retrieval pattern for theplayback device (e.g., assigned slice pillars). Such a determination maybe based on one or more of receiving the retrieval pattern from the settop box 4, generating a new retrieval pattern that is unique as comparedto all previously generated retrieval patterns, and a look up based on aset top box identifier. In an example, the processing module determinesthe retrieval pattern for set top box 4 to include pillars 2-7, 9, 13,15, and 16 when the pillar slicing width is 16, the read threshold is10, and the retrieval pattern has not been assigned to any other set topboxes. Next, the processing module retrieves a unique subset of the setof encoded broadcast data slices based on the retrieval pattern (e.g.,retrieval of slices for pillars 2-7, 9, 13, 15, and 16). Next, theprocessing module sends the unique subset of the set of encodedbroadcast data slices to the playback device (e.g., set top box 4).

In another example of operation, the ingest DS processing 102 receivescontent 108. A method of operation of a processing module (e.g., of theingest DS processing 102) begins with the step where the processingmodule encodes, when enabled, (e.g., when not already stored in the DSNmemory 22, when scheduled, or when requested as discussed previously)broadcast data using an error coding dispersal storage function toproduce a plurality of sets of encoded broadcast data slices. Theprocessing module stores the plurality of sets of encoded broadcast dataslices in the DSN memory 22. Next, the processing module receives aplayback request (e.g., a retrieval request 110) regarding the broadcastdata from a playback device (e.g., a set top box). The processing moduleobtains a unique retrieval matrix for the playback device. The uniqueretrieval matrix includes one or more of a pillars list, a segmentingprotocol, a pre-slice data manipulation function, a forward errorcorrection encoding function, a slicing pillar width, a post-slice datamanipulation function, a write threshold, and a read threshold. Notethat the pillars list includes slice pillar identities of a number ofpillars, wherein the number is between, and including, a slicing pillarwidth number and a read threshold number.

The processing module may obtain the unique retrieval matrix by at leastone of retrieving the unique retrieval matrix from the DSN memory basedon an identity of the playback device and generating the uniqueretrieval matrix. Note that generating the unique retrieval matrix maybe based on one or more of the identity of the playback device, theerror coding dispersal storage function, a data identifier, a uniqueretrieval matrix associated with another playback device, a uniqueretrieval matrix functionality indicator (e.g., a mathematicalmanipulation function) a command, a number of playback requests receivedfor the broadcast data, which combinations of pillars have already beenassigned, a system performance indicator, a cost indicator, asubscription level indicator, a reliability requirement, a reliabilityestimator, a memory utilization indicator, a pillar availabilityindicator, a policy indicator, a total population of set top boxesindicator, and a predetermination. For example, set top box 1 may beassigned a unique retrieval matrix to read from pillars 1-10 and set topbox 2 may be assigned another unique retrieval matrix to read frompillars 3-12 when the system has 16 pillars and a read threshold of 10and both set top boxes have requested the same broadcast data.Alternatively, or in addition to, each set top box is assigned more thanone set of combinations of allowed read pillars to improve readreliability.

Next, the processing module retrieves the plurality of sets of encodedbroadcast data slices from the DSN memory 22 in accordance with theunique retrieval matrix to produce a plurality of unique sets of encodedbroadcast data. The processing module sends the plurality of unique setsof encoded broadcast data to the playback device as retrieved slices112. The operation of the set top boxes 1-V with respect to retrievingslices from the DSN memory 22 or receiving broadcast slices directlyfrom the ingest DS processing unit 102 is discussed in greater detailwith reference to FIG. 10.

FIG. 7 is a flowchart illustrating an example of storing content. Themethod begins with step 114 where a processing module (e.g., of andingest DS processing unit) receives content from one or more of a cabletelevision (TV) system head end, a satellite system head end, a contentprovider, a user device, and a media server. The content may include oneor more of music, video, text, digital rights management (DRM)information, a content type indicator, a content identifier (ID), and acontent size indicator. The DRM information may include one or more of arestriction indicator, a copyright indicator, an open access indicator,and access rights requirements. In an example, the copyright indicatormay indicate that the content portion is copyrighted and the accessrights requirements may indicate access rights that are required toutilize the copyrighted content portion.

The method continues at step 116 where the processing module determinesa DRM policy where the DRM policy may indicate if a content portion isopen to all set top boxes and viewers utilizing similar read operationalparameters (e.g., the same read pillar combinations) or if the contentportion is restricted requiring each set top box to utilize unique readoperational parameters including the read pillar combinations. Such adetermination may be based on one or more of DRM information, thecontent type indicator, the content ID, user base information, systemparameters, content provider information, a command, a vault lookup, apredetermination, and a content size indicator. In an example, theprocessing module determines the DRM policy to be open access when theDRM information indicates that the content portion is not copyrighted.In another example, the processing module determines the DRM policy tobe restricted access when the DRM information indicates that the contentportion is copyrighted and/or included in a list from a contentprovider.

The method continues at step 118 where the processing module determineswrite operational parameters which may include one or more of pillarwidth, dispersed storage (DS) unit identifiers of DS units within adispersed storage network (DSN) memory, a write threshold, a readthreshold, encoding method, slicing method, encryption method, and anencryption key. For instance, the write operational parameters areshared in common with all of the set top boxes utilizing this storageset. Such a determination may be based on one or more of the DRM policy,the DRM information, the content type indicator, the content ID, userbase information, system parameters, content provider information, acommand, a vault lookup, a predetermination, and a content sizeindicator. In an example, the processing module determines the writeoperational parameters to include a pillar width n=32, a write thresholdof 30, and a read threshold of 24. Note that in this example there areover 10 million read pillar combinations (e.g., ways to choose 24 readpillars from 32 pillars).

The method continues at step 120 where the processing module encodes thecontent utilizing an error coding dispersal storage function and inaccordance with the write operational parameters to produce a pluralityof sets of encoded data slices. For instance, the processing moduleappends the DRM policy to the content in accordance with the writeoperational parameters and/or DRM policy prior to the encoding of thecontent. In another instance, the processing module stores the DRMpolicy in a local memory. The method continues at step 122 where theprocessing module sends the encoded data slices to the DSN memory forstorage therein.

FIG. 8A is a flowchart illustrating an example of retrieving content.The method begins with step 124 where a processing module (e.g., of theretrieval dispersed storage (DS) processing unit) receives a contentretrieval message from a requester (e.g., a set top box, a user device,a storage integrity processing unit, a DS managing unit, another DSprocessing unit, a dispersed storage (DS) unit). The retrieval messagemay include a content ID, a user ID, digital rights management (DRM)information, a DRM policy, a content type indicator, content sizeindicator, and/or read operational parameters.

The method continues at step 126 where the processing module determinesa DRM policy where the DRM policy may indicate if a content portion isopen to all set top boxes and viewers utilizing similar read operationalparameters (e.g., the same read pillar combinations) or if the contentportion is restricted requiring each set top box to utilize unique readoperational parameters including the read pillar combinations. Such adetermination may be based on one or more of DRM information, thecontent type indicator, the content ID, user base information, systemparameters, content provider information, a command, a vault lookup, apredetermination, and a content size indicator.

The method continues at step 128 where the processing module determinesread operational parameters for the requester which may include one ormore of pillar width, allowed DS units of a dispersed storage network(DSN) memory to retrieve slices, a write threshold, a read threshold,decoding method, de-slicing method, decryption method, and a decryptionkey. For instance, the read operational parameters may be shared incommon with all of the set top boxes utilizing a common DS unit storageset when the DRM policy indicates open access. In another instance, theread operational parameters may be substantially unique for each top boxutilizing a common DS unit storage set when the DRM policy indicatesrestricted access. Such a determination may be based on one or more ofthe DRM policy, the DRM information, the content type indicator, thecontent ID, user base information, system parameters, content providerinformation, a command, a vault lookup, a user vault lookup, apredetermination, a command, and/or a content size indicator. In anexample, the processing module may determine the read operationalparameters to include a pillar width n=32, a read threshold of 24, andone allowed pillar set combination of pillars 1-12, 15-20, 22-29.

The method continues at step 130 where the processing module retrievesencoded data slices from the allowed pillars of the DSN memory inaccordance with the read operational parameters and/or DRM policy. Next,the processing module decodes the encoded data slices utilizing an errorcoding dispersal storage function and in accordance with the readoperational parameters to produce a content portion. The methodcontinues at step 132 where the processing module sends the contentportion and/or the encoded data slices to the requester. The method toprocess a content retrieval message is discussed in greater detail withreference to FIGS. 13-15, and FIGS. 18-19.

FIG. 8B is a flowchart illustrating another example of retrievingcontent. In particular, a method is presented for use in conjunctionwith one or more functions and features described in conjunction withFIGS. 1-5, 8A, and also FIG. 8B. The method includes step 125 where aprocessing module of one or more computing devices of a centralizeddigital video storage (DVS) system that supports a plurality ofsubscriber units, receives a request for playback of a storedmulti-media file of a plurality of stored multi-media files from asubscriber unit of the plurality of subscriber units. The centralizedDVS system stores the plurality of stored multi-media files as aplurality of dispersed storage error encoded data objects. One of theplurality of dispersed storage error encoded data objects corresponds tothe stored multi-media file and includes a plurality of sets of encodeddata slices.

Each of the plurality of subscriber units is assigned a unique sliceretrieval pattern. The unique retrieval pattern includes one or more ofa pillars list, a segmenting protocol, a pre-slice data manipulationfunction, a forward error correction encoding function, a slicing pillarwidth, a post-slice data manipulation function, a write threshold, and aread threshold. Alternatively, or in addition to, the processing modulereceives a second request for playback of a second stored multi-mediafile of the plurality of stored multi-media files from the subscriberunit, where another one of the plurality of dispersed storage errorencoded data objects corresponding to the second stored multi-media fileincludes a second plurality of sets of encoded data slices.

The method continues at step 127 where the processing module determineswhether the stored multi-media file is a subscription based file or apublically available file. As a specific example, the processing moduleaccesses a listing of the plurality of multi-media files to determinewhether the stored multi-media file is the subscription based file orthe publically available file. Alternatively, or in addition to, theprocessing module determines whether the second stored multi-media fileis the subscription based file or the publically available file whenreceiving the second request for playback of the second storedmulti-media file from the subscriber unit. The method branches to step131 when the stored multi-media file is the subscription based file. Themethod continues to step 129 when the stored multi-media file is apublicly available file.

When the stored multi-media file is the publicly available file, themethod continues at step 129 where the processing module sends a uniquecopy of the stored multi-media file to the subscriber unit in accordancewith the unique slice retrieval pattern of the subscriber unit. Theunique slice retrieval pattern of the subscriber unit further indicatesthe unique pattern for identifying the decode threshold number ofencoded data slices of a second plurality of sets of encoded dataslices. The method branches to step 135.

When the stored multi-media file is the subscription based file, themethod continues at step 131 where the processing module accessesdigital rights management data regarding subscription based multi-mediafiles to determine the subscriber unit's digital rights to the storedmulti-media file. The digital rights management data includes one ormore rights from a list of rights, where the list of rights includes acontent identifier for each subscription based file of the plurality ofstored multi-media files, a subscriber identifier for at least some ofthe plurality of subscriber units, subscriber based access privilegeswith respect to subscription based files, and a logical storage vaultidentifier associated with one or more of the subscription based files.Alternatively, or in addition to, the processing module accesses thedigital rights management data to determine the subscriber unit'sdigital rights to the second stored multi-media file when the secondstored multi-media file is the subscription based file and whenreceiving the second request for playback of the second storedmulti-media file from the subscriber unit.

When the subscriber unit's digital rights include playback of themulti-media file, the method continues at step 133 where the processingmodule sends a unique copy of the stored multi-media file to thesubscriber unit in accordance with the unique slice retrieval pattern ofthe subscriber unit. The unique slice retrieval pattern of thesubscriber unit indicates a unique pattern for identifying a decodethreshold number of encoded data slices of the plurality of sets ofencoded data slices. Alternatively, or in addition to, the processingmodule sends a unique copy of the second stored multi-media file to thesubscriber unit in accordance with the unique slice retrieval pattern ofthe subscriber unit when the subscriber unit's digital rights includeplayback of the second stored multi-media file and when receiving thesecond request for playback of the second stored multi-media file fromthe subscriber unit. The unique slice retrieval pattern of thesubscriber unit indicates the unique pattern for identifying the decodethreshold number of encoded data slices of the second plurality of setsof encoded data slices.

The method continues at step 135 where the processing module receives,from a second subscriber unit of the plurality of subscriber units, asecond request for playback of the stored multi-media file. The methodcontinues at step 137 where the processing module accesses the digitalrights management data to determine the second subscriber unit's digitalrights to the stored multi-media file. When the second subscriber unit'sdigital rights include playback of the stored multi-media file, themethod continues at step 139 where the processing module sends a secondunique copy of the stored multi-media file to the second subscriber unitin accordance with the unique slice retrieval pattern of the secondsubscriber unit. The unique slice retrieval pattern of the secondsubscriber unit indicates a second unique pattern for identifying thedecoded threshold number of encoded data slices of the plurality of setsof encoded data slices.

Alternatively, or in addition to, the processing module receives, fromthe subscriber, a request for one right from a set of rights, where theset of rights include copying, publicly displaying, distributing, andmaking derivative works, wherein the request identifies the storedmulti-media file. Having received the request for the one right, theprocessing module accesses the digital rights management data todetermine the subscriber unit's digital rights to the stored multi-mediafile. When the subscriber unit's digital rights include the one rightfrom the set of rights, the processing module sends the unique copy ofthe stored multi-media file to the subscriber unit in accordance withthe unique slice retrieval pattern of the subscriber unit.

The method described above in conjunction with a processing module canalternatively be performed by other modules of a dispersed storagenetwork or by other devices. In addition, at least one memory sectionthat stores operational instructions can, when executed by one or moreprocessing modules of one or more computing devices of a dispersedstorage network (DSN), cause the one or more computing devices toperform any or all of the method steps described above.

FIG. 9 is another schematic block diagram of another embodiment of acomputing system. As illustrated, the system includes at least oneingest dispersed storage (DS) processing unit 102, a dispersed storagenetwork (DSN) memory 22, a retrieval DS processing unit 104, adistribution network 106, at least one cache module 134, a plurality ofset top boxes 1-V, and a plurality of viewers 1-V. The DSN memory 22includes a plurality of DS units 1-n. The distribution network 106 mayinclude one or more of a hybrid fiber coax system, a satellite system,an internet access system, and a wireless system. The set top boxes 1-Vinclude the computing core 26 of FIG. 2 DS processing 34 toreceive/retrieve content slices, de-slice, and decode to produce thecontent for consumption (e.g., viewing). The viewers 1-V may beimplemented with a flat panel television including a display andspeakers to reproduce content. As illustrated, the ingest DS processingunit 102 and the retrieval DS processing unit 104 are implemented as atleast two units. In another implementation example, the ingest DSprocessing unit 102 and the retrieval DS processing unit 104 areimplemented in the same unit. In yet another implementation example, theingest DS processing unit 102 and/or the retrieval DS processing unit104 are implemented as part of at least one of the set top boxes 1-V. Inyet another implementation example, the DSN memory 22 is implemented inone or more of the set top boxes 1-V. The cache module 134 may beimplemented utilizing the computer core 26 of FIG. 2 and may further beimplemented as an independent unit and/or in one or more of the set topboxes 1-V serving a plurality of set top boxes (e.g., common to abuilding or a neighborhood).

The ingest DS processing unit 102 stores at least a portion of content108 in the DSN memory 22. The retrieval DS processing unit 104 retrievesat least a portion of the content 108 from the DSN memory 22 and sendsthe content 108 as retrieved slices 112 via the distribution network 106to one or more of the set top boxes 1-V for consumption by one or moreof the viewers 1-V. The viewers 1-V reproduce content (e.g., video,audio, pictures, web content) output from the corresponding set topboxes 1-V. The set top boxes 1-V may select live broadcast content(e.g., broadcast/multicast or on-demand video over cable, satelliteand/or the internet) and/or stored content from the DSN memory 22 viathe cache module 134 and/or the retrieval DS processing unit 104.

The set top boxes 1-V send retrieval request 110 messages to theretrieval DS processing unit 104, the cache module 134, and/or DSNmemory 22 that include control commands. The commands may include one ormore of record, playback, pause, skip forward, skip backwards, selectbroadcast content, and delete. For example, the ingest DS processingunit 102 may store a portion of the content 108 in the DSN memory 22 inresponse to a record command from set top box 6 and the retrieval DSprocessing unit 104 may retrieve a portion of the content from the DSNmemory 22 and send it to one or more of the cache module 134, the viewer6, and/or the set top box 6 in response to receiving a playback commandfrom set top box 6.

The cache module 134 retrieves slices and/or content portion slicestreams 112 from the retrieval DS processing unit 104 and/or the DSNmemory 22, temporarily saves the slices in memory of the cache module134, sends at least some of the slices to at least one or more set topboxes 1-V, and deletes the slices saved in the memory of the cachemodule 134. In an example of operation, the cache module 134 determineswhich slices to save in memory of the cache module 134 based on one ormore of content portion requests/commands from set top boxes/viewers,monitoring of slice streams (e.g., slice streams from the DSN memory 22to the set top boxes 1-V), a vault lookup, a system performanceindicator, a distribution network performance indicator, a command, anda predetermination. In an example, the cache module 134 determines tosave slice streams 112 for set top boxes 2 and 3 when set top boxes 2and 3 are receiving substantially the same content (e.g., at least someof the same slice pillars). Note that set top boxes 2 and 3 may beviewing the same live broadcast or may be downloading the same contentportion for subsequent viewing. Further note that set top boxes 2 and 3may not be retrieving the same exact pillars from the DSN memory 22since they may be utilizing different read operational parametersincluding different read pillars. In an example, cache module 134retrieves slices of the common read pillars from the DSN memory 22and/or the retrieval DS processing unit 104 on behalf of set top boxes 2and 3 in one set of slice streams from the DSN memory 22 through thedistribution network 106 rather than in two slice streams through thedistribution network 106. Note that the method of the cache module 134may provide an improved utilization of the available capacity of thedistribution network 106, the DSN memory 22, and/or the retrieval DSprocessing unit 104.

In another example of operation of the cache module 134, the cachemodule 134 determines that set top box 2 and set top box 3 haverequested the same content portion (e.g., from the playback command,monitoring slice streams in progress). The cache module 134 sends aproxy message (e.g., a retrieval request 110) to the retrieval DSprocessing unit 104 where the proxy message indicates that the retrievalDS processing unit 104 is requested to send one set of common pillarslices via the distribution network 106 to the cache module 134 ratherthan sending two sets of the same slices to the individual set top boxes2 and 3. Next, the cache module 134 receives the common set of pillarslices (e.g., retrieve slices 112) from the retrieval DS processing unit104 and temporarily saves the slices in the memory of the cache module134. The cache module 134 retrieves a subset of slices associated withset top box 2 of the slices from the memory of the cache module andsends the subset of slices to set top box 2. The cache module 134retrieves a subset of slices associated with set top box 3 of the slicesfrom the memory of the cache module and sends the subset of slices toset top box 3. For instance, a connection from the cache module 134 tothe set top boxes 2 and 3 may be provided via a common neighborhood coaxsubsystem that is partitioned from the primary distribution network 106.

In an example of operation, the ingest DS processing unit 102 determineswhich portion of the content 108 to store in the DSN memory 22 forsubsequent retrieval (e.g., immediately, minutes, hours, days, and evenyears later) and consumption by one or more of the set top boxes 1-V.Such a determination may be based on one or more of a command, a commandfrom the set top box, a command from the retrieval DS processing unit, acommand from a DS managing unit, a DSN memory status indictor, and apredetermination. In an example, the ingest DS processing 102 determinesto store all of the received content 108 based on a predetermination.For instance, the ingest DS processing unit 102 continuously stores allcontent 108 from a 500 channel cable TV distribution system. The set topboxes 1-V may retrieve slices and/or content immediately and/or at atime much later than the original reception of the content by the ingestDS processing unit 102. For instance, the set top boxes 1-V retrievecontent from the DSN memory 22 immediately after the content 108 wasstored in the DSN memory 22 to mimic broadcast reception. In anotherinstance, the set top boxes 1-V may retrieve content from the DSN memory22 hours, days, months, or even years after the content of 108 wasstored in the DSN memory 22 to mimic digital video recorder playback.

In another example of operation, the ingest DS processing unit 102determines to store content selected by one or more of the plurality ofset top boxes 1-V. For instance, set top box 2 sends a record command tothe ingest DS processing unit 102 where the record command includes acommand to record the 5:30 pm evening news on cable channel 188 onOctober 18. The ingest DS processing unit 102 processes the recordcommand which may include saving the store command for future execution.The ingest DS processing unit 102 executes the store command on October18 at 5:30 pm by selecting the content from cable channel 188, receivingthe content, determining write operational parameters (e.g., pillarwidth n, write threshold, encoding method, slicing method, encryptionmethod, etc.), encoding the content utilizing an error coded dispersedstorage function and in accordance with write operational parameters toproduce a plurality of sets of encoded data slices, determining which DSunits to store the plurality of sets of encoded data slices, and sendingthe plurality of sets of encoded data slices to the DSN memory 22 with astore command for storage in the selected DS units. Note that the ingestDS processing unit 102 determines the write operational parameters basedon one or more of a command, a command from the retrieval DS processingunit, an estimated number of store commands received for the samecontent indicator, a system performance indicator, a memory utilizationindicator, a policy indicator, a total population of set top boxesindicator, and a predetermination.

Note that multiple set top boxes may send the ingest DS processing unit102 a record command specifying the same content portion. In an example,the ingest DS processing unit 102 stores slices created from the contentportion in response to receiving at least one record command for thecontent portion from at least one set top box. The ingest DS processingunit 102 determines if it has received record commands for the samecontent portion (e.g., check a table of pending record operations) andprocesses the record commands in accordance with the determination. Inanother example, the ingest DS processing unit 102 queues the storecommand based on receiving a first record command for the contentportion and queues nothing when receiving a second record command forthe same content portion as the first record command. In other words,the first record command for a given content portion invokes storing thecontent as slices to the DSN memory 22 and any other subsequent recordcommands for the same content do not change the storing of that contentportion as slices in the DSN memory 22.

In another example of operation, the ingest DS processing unit 102queues the store command based on receiving a first record command forthe content portion and queues another store command when receiving asecond (or subsequent) record command for the same content portion asthe first record command. The ingest DS processing unit 102 maydetermine different write operational parameters based on receiving twoor more store commands for the same content portion. Such adetermination may be based on one or more of a command, a command fromthe retrieval DS processing unit, the number of store commands receivedfor the same content portion, a system performance indicator, a memoryutilization indicator, a policy indicator, a total population of set topboxes indicator, and a predetermination.

Note that the ingest DS processing unit 102 may receive a record/storecommand after the content (e.g., a live broadcast stream) has beenstarted to be received but before it has all been received (e.g., partway in a real time broadcast). The ingest DS processing unit 102 maydetermine the same or different write operational parameters for acontent recording in progress when an incremental record command forthat content is received.

The ingest DS processing unit 102 processes the record command (e.g.,from the viewer/set top box) including determining read operationalparameters for the viewer for this content portion (e.g., pillar widthn, which particular pillars are allowed to read, read threshold,decoding method, de-slicing method, decryption method, etc.). In anexample, the ingest DS processing unit 102 performs the determinationwhen the ingest DS processing unit 102 receives the record command. Inanother example, the retrieval DS processing unit 104 may make the readoperational parameters determination when the retrieval DS processingunit 104 receives a playback command from a viewer/set top box. Ineither example, the determination may be based on one or more of acommand, the number of store commands received for the same contentportion, an estimated number of store commands received for the samecontent portion indicator, which combinations of pillars have alreadybeen assigned (e.g., the read operational parameters of other viewers),a system performance indicator, a cost indicator, a subscription levelindicator, a reliability requirement, a reliability estimator, a memoryutilization indicator, a pillar availability indicator, a policyindicator, a total population of set top boxes indicator, and apredetermination.

In an example, set top box 1 is assigned read operational parameters toread from pillars 1-10 and set top box 2 is assigned read operationalparameters to read from pillars 3-12 when the system has 16 pillars anda read threshold of 10 and both set top boxes have requested the samecontent portion. In another example, each set top box is assigned morethan one set of combinations of allowed read pillars to improve readreliability. For instance, the retrieval DS processing 104 may utilizeone or more of the allowed read pillar sets of the read operationalparameters (e.g., for the particular set top box) to convert retrievedslices from the allowed read pillars into the desired content portion.In another instance, a DS processing of the set top box may utilize oneor more of the allowed read pillar sets of the read operationalparameters (e.g., for the particular set top box) to convert retrievedslices 112 from the allowed read pillars into the desired contentportion. The method of operation of the system to store and retrievecontent is discussed in greater detail with reference to FIGS. 10-19.

FIG. 10 is another schematic block diagram of another embodiment of acomputing system. As illustrated, the system includes at least oneingest dispersed storage (DS) processing unit 102, a dispersed storagenetwork (DSN) memory 22, a retrieval DS processing unit 104, adistribution network 106, a plurality of set top boxes 1-V, and aplurality of viewers 1-V. The DSN memory 22 includes a plurality ofdispersed storage (DS) units 1-n as previously discussed. Alternatively,the DSN memory 22 is implemented in one or more of the set top boxes1-V. The ingest DS processing unit 102 and the retrieval DS processingunit 104 functions include those discussed previously (e.g., of FIGS.1-9) and additional functionality as discussed with reference to FIGS.10-26. Alternatively, the ingest DS processing unit 102 and theretrieval DS processing unit 104 are implemented in the same DS unit 16.Alternatively, the ingest DS processing unit 102 and the retrieval DSprocessing unit 104 are implemented in at least one of set top boxes1-V. Note that the ingest DS processing unit 102 may be operably coupledto the retrieval DS processing unit 104 to facilitate exchangesincluding commands and content. The distribution network 106 may beimplemented utilizing one or more of a hybrid fiber coax system, asatellite system, an internet access system, and a wireless system.

The set top boxes 1-V include the computing core 26 of FIG. 2 and a DSprocessing 34. The set top boxes 1-V reproduce broadcast data in aformat compatible with the viewers 1-V. The viewers 1-V may include adisplay and speakers such as a flat panel television to reproducebroadcast data. As illustrated, the plurality of set top boxes 1-V isoperably coupled via the distribution network 106 to the retrieval DSprocessing unit 104. As illustrated the set top boxes 1-V are operablycoupled directly to the ingest DS processing unit 102. Alternatively, orin addition to, the set top boxes 1-V are operably coupled directly tothe DS units 1-n. Alternatively, the functions of the set top boxes 1-Vand viewer 1-V are integrated together. In an example, viewer 3 (e.g.,including set top box 3 functionality) may be operably coupled to theretrieval DS processing unit 104, to the ingest DS processing unit 102,and to the DSN memory 22.

As previously discussed, the ingest DS processing 102 receives content108 as broadcast data and a processing module encodes a portion of thebroadcast data using an error coding dispersal storage function toproduce a set of encoded broadcast data slices, sends the set of encodedbroadcast data as pillars 1-n slices 136 to set top boxes 1-V when theset of encoded broadcast data slices was not compressed or sends asubset of encoded broadcast data slices as broadcast slices 138 to settop boxes 1-V when the set of encoded broadcast data slices wascompressed. As previously discussed, the processing module sends the setof encoded broadcast data slices (e.g., as illustrated: pillar 1 slices,pillar 2 slices, through pillar n slices) to the DSN memory 22 forstorage therein.

In an example of operation of a playback device (e.g., a set top box), aprocessing module obtains a unique retrieval matrix based on an identityof the playback device. The unique retrieval matrix includes one or moreof a pillars list, a segmenting protocol, a pre-slice data manipulationfunction, a forward error correction encoding function, a slicing pillarwidth, a post-slice data manipulation function, a write threshold, and aread threshold. Note that the pillars list includes slice pillaridentities of a number of pillars, wherein the number is between, andincluding a slicing pillar width number and a read threshold number.

The processing module may obtain the unique retrieval matrix by at leastone of retrieving the unique retrieval matrix from the DSN memory 22based on an identity of the playback device and generating the uniqueretrieval matrix. Note that generating the unique retrieval matrix maybe based on one or more of an identity of a previously received subsetof a previous set of encoded broadcast data slices, the identity of theplayback device, an error coding dispersal storage function, a dataidentifier, a unique retrieval matrix associated with another playbackdevice, a unique retrieval matrix functionality indicator (e.g., amathematical manipulation function) a command, a number of playbackrequests received for the broadcast data, which combinations of pillarshave already been assigned, a system performance indicator, a costindicator, a subscription level indicator, a reliability requirement, areliability estimator, a memory utilization indicator, a pillaravailability indicator, a policy indicator, a total population of settop boxes indicator, and a predetermination. For example, set top box 1may be associated with a unique retrieval matrix to read from pillars1-10 and set top box 2 may be associated with another unique retrievalmatrix to read from pillars 3-12 when the system has 16 pillars and aread threshold of 10 and both set top boxes have requested the samebroadcast data. Alternatively, or in addition to, each set top box mayutilize more than one set of combinations of allowed read pillars toimprove read reliability.

The example of operation continues with the step where the processingmodule sends a request for retrieval (e.g., a retrieval request 110) ofa set of encoded broadcast data slices to the DSN memory 22, wherein therequest includes the unique retrieval matrix and an identity of the setof encoded broadcast data slices. Alternatively, the processing modulemay send the request for retrieval to the retrieval DS processing unit104. The processing module receives a subset of the set of encodedbroadcast data slices (retrieved slices 112) from the DSN memory 22(directly or via the retrieval DS processing unit 104) via thedistribution networks 106, wherein the subset of the set of encodedbroadcast data slices is based on the unique retrieval matrix. Next, theprocessing module stores (e.g., in a slice buffer) the subset of thesets of encoded broadcast data slices. The processing module decodes thesubset of the set of encoded broadcast data slices using an error codingdispersal storage function and in accordance with the unique retrievalmatrix to produce a portion of broadcast data.

Note that the set top boxes 1-V may receive live broadcast slices 138from the ingest DS processing unit 102 and switch to retrievingretrieved slices 112 from the retrieval DS processing unit when the settop box can no longer consume the live broadcast slices 138 (e.g., apause mode) as described below. In an example of operation, theprocessing module of set top box 5 receives, during a live broadcast ofa portion of broadcast data, the set of encoded broadcast data slices138 (e.g., from the ingest DS processing unit 102). Next, the processingmodule detects a pause function of the live broadcast (e.g., a set topbox 3 user input) and buffers subsequent sets of encoded broadcast dataslices in a slice buffer while the pause function is active. Note thatthe slice buffer of set top box 3 may have a memory capacity that issubstantially less than the memory capacity of the DSN memory 22. In anexample, the slice buffer has a one-minute of broadcast content memorycapacity.

Next, the processing module determines whether a slice buffer indicatorof the slice buffer compares unfavorably with a slice buffer threshold.For instance, the slice buffer indicator indicates the magnitude ofutilization of the slice buffer. In an example, the processing moduledetermines that the comparison is unfavorable when the slice bufferindicator is greater than the slice buffer threshold (e.g., the bufferis filling up). The method branches to the step where the processingmodule determines whether the slice buffer indicator comparesunfavorably with a second slice buffer threshold when the processingmodule determines that the slice buffer indicator does not compareunfavorably to the slice buffer threshold. The method continues to thenext step when the processing module determines that the slice bufferindicator does compare unfavorably to the slice buffer threshold. In thenext step, the processing module ceases the buffering of the subsequentset of encoded broadcast data slices 138. The processing module detectsa resume function of the live broadcast (e.g., a play command user inputhas been received by the set top box 3). Next, the processing moduleretrieves the subsequent sets of encoded broadcast data slices from theslice buffer when the resume function is detected.

The example of operation continues with the step where the processingmodule determines whether the slice buffer indicator comparesunfavorably with a second slice buffer threshold. In an example, theprocessing module determines that the comparison is unfavorable when theslice buffer indicator is less than the second slice buffer threshold(e.g., the buffer is emptying out). In another example, the processingmodule determines that the comparison is unfavorable when the slicebuffer indicator is less than the second slice buffer threshold andrecent broadcast slices stored within the slice buffer are older thancurrent broadcast slices 138 being broadcast live. Note that thisscenario may happen when the slice buffer is filled while on pause andlive broadcast continues.

The processing module continues to receive live broadcast slices 138when the processing module determines that a slice buffer indicator doesnot compare unfavorably with the second slice buffer threshold. Themethod continues to the next step when the when the processing moduledetermines that slice buffer indicator compares unfavorably with thesecond slice buffer threshold. In the next step, the processing modulesends a request for retrieval 110 of another subsequent set of encodedbroadcast data slices to the DSN memory 22 and/or to the retrieval DSprocessing unit 104. The processing module receives a subset of theother subsequent set of encoded broadcast data slices as retrievedslices 112 from the DSN memory 22, wherein the subset of the othersubsequent set of encoded broadcast data slices is based on the uniqueretrieval matrix. The processing module stores the subset of the othersubsequent set of encoded broadcast data slices in the slice buffer. Theprocessing module decodes the set of encoded broadcast slices using theerror coding dispersal storage function to recapture the portion of thebroadcast data during the live broadcast of the portion of the broadcastdata.

FIG. 11 is an illustration of an example content ingestion table 140. Asillustrated, the content ingestion table 140 includes a contentidentifier (ID) 142 field and a content timestamp 144 field. In anexample of operation, an ingest DS processing unit populates the contentingestion table 140 upon ingestion of content. For instance, the ingestDS processing unit receives the content, determines the content ID,determines a current timestamp (e.g., a system clock), and stores thecontent ID in the content ID 142 field and stores the current timestampas the content timestamp in the content timestamp 144 field of thecontent ingestion table 140. The current timestamp determination may bebased on one or more of a system clock, an ingest dispersed storage (DS)processing unit clock, a command, a message, and a query. In anotherexample of operation, the ingest DS processing unit receives content onDec. 25, 2001 at 3 PM that includes a content portion with a content IDof A1. The ingest DS processing unit adds an entry to the contentingestion table 140 that includes the content ID of A1 in the content ID142 field and a content timestamp of Dec. 25, 2001 at 3 PM in thecontent timestamp 144 field.

A retrieval DS processing unit may utilize information from the contentingestion table 140 to determine when the content was ingested into adispersed storage network (DSN) memory. In an example, the retrieval DSprocessing unit may retrieve the content from the DSN memory and send itto a requester if the requester had access rights to the content at thetime when the content was ingested. The method of the retrieval DSprocessing unit to retrieve content based in part on the access rightsis discussed in greater detail with reference to FIGS. 13-15.

FIG. 12 is an illustration of an example user access rights table 146.As illustrated, the user access rights table 146 includes a useridentifier (ID) 148 field, a content ID 150 field, a start timestamp 152field, and an end timestamp 154 field. In an example of operation, adispersed storage (DS) managing unit populates the user access rightstable 146 and may be based on content subscription information. Asillustrated, user ID 2 had access to content ID A1 with a starttimestamp of Sep. 3, 2000 1 PM until an end timestamp of Mar. 9, 2001 at8 PM. User ID 1 has access to content A2 from Nov. 18, 2009 at 1 PMuntil the present time.

In an example of operation, a retrieval DS processing unit utilizes theuser access rights table 146 to determine if a requester has sufficientaccess rights to requested content. In an example, the retrieval DSprocessing unit determines if the requester had access rights when thecontent was ingested into a dispersed storage network (DSN) memory. Forinstance, the retrieval DS processing unit receives a retrieval requestmessage for content ID A1 from a requester with a user ID 1. Theretrieval DS processing unit obtains information from a contentingestion table 140 to determine that the content timestamp for contentID A1 is Dec. 25, 2001 at 3 PM. The retrieval DS processing unit obtainsinformation from the user access rights table 146 to determine that theuser ID 1 had content ID A1 access rights from Oct. 1, 2001 at 5 PM toJul. 28, 2002 at 6 PM. The retrieval DS processing unit retrievescontent ID A1 from the DSN memory and sends content ID A1 to therequester since the user ID had sufficient access rights when content A1was ingested into the DSN memory.

In another example, the retrieval DS processing unit may determine ifthe user currently has access rights. For instance, the retrieval DSprocessing unit receives a retrieval request message for content ID A1from a requester with a user ID 1. The retrieval DS processing unitobtains information from the content ingestion table 140 to determinethat the content timestamp for content ID A1 is Dec. 25, 2001 at 3 PM.The retrieval DS processing unit obtains information from the useraccess rights table 146 to determine that the user ID 1 had content IDA1 access rights from Oct. 1, 2001 at 5 PM to Jul. 28, 2002 at 6 PM. Theretrieval DS processing unit determines that the current timestamp isDec. 27, 2009 at 3 PM. The retrieval DS processing unit does notretrieve content ID A1 from the DSN memory since the user ID does notcurrently have sufficient access rights to content A1. The method of theretrieval DS processing unit to retrieve content based in part on theaccess rights is discussed in greater detail with reference to FIGS.13-15.

FIG. 13 is another flowchart illustrating another example of retrievingcontent. The method begins with step 156 where a processing module(e.g., of a retrieval dispersed storage (DS) processing unit) receives acontent retrieval message from a requester. The requester may includeone or more of a set top box, a user device, a DS managing unit, astorage integrity processing unit, another DS processing unit, a DSunit, and another source. The retrieval message may include a contentidentifier (ID), a user ID, a content type indicator, digital rightsmanagement (DRM) information, a DRM policy, and read operationalparameters.

The method continues at step 158 where the processing module determinesuser access rights based on one or more of the content ID, the user ID,a user access rights table lookup, a content type indicator, DRMinformation, DRM policy, user base information, system parameters, andread operational parameters. The method continues at step 160 where theprocessing module determines a content timestamp based on one or more ofthe content ID, the user ID, a content timestamp table lookup, a useraccess rights table lookup, a content type indicator, DRM information,DRM policy, user base information, system parameters, and readoperational parameters. The method continues at step 162 where theprocessing module determines the current timestamp as discussedpreviously with reference to FIGS. 11-12.

The method continues at step 164 where the processing module determinesif the user access rights compare favorably to the content timestamp andcurrent timestamp. In an example, the processing module determines ifthe user had access rights at the time of content ingestion into adispersed storage network (DSN) memory. In another example theprocessing module determines if the user currently has access rights tothe content. The method of determining if the user access rights comparefavorably to the timestamps is discussed in greater detail withreference to FIGS. 14-15. The method branches to step 170 when theprocessing module determines that the user access rights comparefavorably to the timestamps. The method continues to step 166 when theprocessing module determines that the user access rights do not comparefavorably to the timestamps.

The method continues at step 166 where the processing module determinesif the user access rights can be modified. In an example, the processingmodule may query a DS managing unit to request a modification to theuser access rights. In another example, the processing module sends amessage to the requester to determine if the user access rights can bemodified (e.g., sell immediate access). The method to determine if theuser access rights can be modified is discussed in greater detail withreference to FIG. 16. The method repeats back to step 158 when theprocessing module determines that the user access rights can bemodified. The method ends at step 168 where the processing module sendsan error message (e.g., to the requester and/or the DS managing unit)when the processing module determines that the user access rights cannotbe modified.

The method continues at step 170 where the processing module determinesread operational parameters when the processing module determines thatthe user access rights compare favorably to the timestamps. The readoperational parameters may include one or more of the pillar width, readthreshold, pillars allowed to retrieve from, a decode method, a de-slicemethod, a decryption method, a decryption key, and pillar combinationsfor this requester. Such a determination may be based on one or more ofthe content ID, the user ID, a user access rights table lookup, acontent ingestion table lookup, a content type indicator, DRMinformation, DRM policy, user base information, system parameters, and avault lookup. The method continues at step 172 where the processingmodule retrieves encoded data slices from the DSN memory and decodes theencoded data slices utilizing an error coding dispersed storage functionand in accordance with the read operational parameters produce thecontent. The method continues at step 174 where the processing modulesends the content and/or the encoded data slices to the requester.

FIG. 14 is a flowchart illustrating an example of determining useraccess rights. The method begins with step 176 where a processing moduledetermines if each of a plurality of users has access to a requestedcontent identifier (ID). Such a determination may be based on one ormore of the content ID, a user ID, a user access rights table lookup, acontent ingestion table lookup, a global content access list, a contenttype indicator, digital rights management (DRM) information, a DRMpolicy, user base information, system parameters, and a vault lookup.The method branches to step 182 when the processing module determinesthat each of the plurality of users have access to the content ID. Themethod continues to step 178 when the processing module determines thateach of the plurality of users do not have access to the content ID. Themethod continues at step 178 where the processing module determines if astart timestamp is before a content timestamp based on a comparison ofthe two timestamps. The method branches to step 184 when the processingmodule determines that the start timestamp is not before the contenttimestamp. The method continues to step 180 when the processing moduledetermines that the start timestamp is before the content timestamp.

The method continues at step 180 where the processing module determinesif an end timestamp is after the content timestamp based on a comparisonof the two timestamps. The method branches to step 182 when theprocessing module determines that the end timestamp is after the contenttimestamp. The method continues to step 184 when the processing moduledetermines that the end timestamp is not after the content timestamp.The method continues at step 184 where the processing module indicatesthat the access rights do not compare favorably to the timestamps whenthe processing module determines that the end timestamp is not after thecontent timestamp or when the processing module determines that thestart timestamp is not before the content timestamp. The methodcontinues at step 182 where the processing module indicates that theaccess rights compare favorably to the timestamps when the processingmodule determines that the end timestamp is after the content timestampor when each of the plurality of users have access to the content ID.

FIG. 15 is another flowchart illustrating another example of determininguser access rights. The method begins with step 186 where a processingmodule determines if each of a plurality of users has access to arequested content ID. Such a determination may be based on one or moreof the content ID, a user ID, a user access rights table lookup, acontent ingestion table lookup, a global content access list, a contenttype indicator, digital rights management (DRM) information, a DRMpolicy, user base information, system parameters, and a vault lookup.The method branches to step 192 when the processing module determinesthat each of the plurality of users have access to the content ID. Themethod continues to step 188 when the processing module determines thatall users do not have access to the content ID. The method continues atstep 188 where the processing module determines if a start timestamp isbefore a current timestamp by comparing the two timestamps. The methodbranches to step 194 when the processing module determines that thestart timestamp is not before the current timestamp. The methodcontinues to step 190 when the processing module determines that thestart timestamp is before the current timestamp.

The method continues at step 190 where the processing module determinesif an end timestamp is before the current timestamp by comparing the twotimestamps. The method branches to step 192 when the processing moduledetermines that the end timestamp is not before the current timestamp.The method continues to step 194 when the processing module determinesthat the end timestamp is before the current timestamp. The methodcontinues at step 194 where the processing module indicates that theaccess rights do not compare favorably to the timestamps when theprocessing module determines that the end timestamp is before thecurrent timestamp or when the processing module determines that thestart timestamp is not before the current timestamp. The methodcontinues at step 192 where the processing module indicates that theaccess rights compare favorably to the timestamps when the processingmodule determines that the end timestamp is not before the currenttimestamp or when each of the plurality of users have access to thecontent ID.

FIG. 16 is a flowchart illustrating an example of modifying user accessrights. The method begins with step 196 where a processing module sendsa modification request message to a requester. Such a notificationrequest message may include one or more of a content identifier (ID), auser ID, digital rights management (DRM) information, a DRM policy,content type, and modification information. The modification informationmay include modification requirements (e.g., insufficient access rightwhen the content was ingested by a dispersed storage network (DSN)memory, insufficient current access rights) and/or pricing informationfor access rights modification.

The method continues at step 198 where the processing module receives amodification request response message from the requester where themessage may include one or more of content ID, user ID, subscriptioninformation, payment information, DRM information, DRM policy, contenttype, and modification information. In an example, the processing modulemay receive the modification request response message that includes apayment of five dollars to enable a user to have immediate access torequested content.

The method continues at step 200 where the processing module determinesif the modification request response message is favorable to modifyaccess rights. Such a determination may be based on one or more ofcontent ID, user ID, subscription information, payment information, acomparison of the payment information to the modification information, acomparison of subscription information to the required subscription, DRMinformation, DRM policy, content type, and modification information. Inan example, the processing module determines that the response messageis favorable when the payment information is sufficient to gain accessrights. The method branches to step 204 when the processing moduledetermines that the modification request response message is favorableto modify the access rights. The method continues to step 202 when theprocessing module determines that the modification request responsemessage is not favorable to modify access rights. The method continuesat step 202 where the processing module indicates that the access rightsare not modified.

The method continues at step 204 where the processing module modifiesthe access rights when the processing module determines that themodification request response message is favorable to modify accessrights. In an example, the processing module modifies the user accessrights by changing an entry in a user access rights table such that astart timestamp and an end timestamp wrap around a content timestamp toenable content access when content access rights at the time ofingestion into the DSN memory are required. In another example, theprocessing module modifies the user access rights by changing an entryin the user access rights table such that the end timestamp is notbefore the current timestamp to enable content access when contentaccess rights at the current timestamp are required. The methodcontinues at step 206 where the processing module sends an indicationmessage to indicate that the access rights are modified. In an instance,the processing module sends the indication message to a dispersedstorage (DS) managing unit.

FIG. 17A is another schematic block diagram of another embodiment of acomputing system. As illustrated, the system includes at least oneingest dispersed storage (DS) processing unit 102, a dispersed storagenetwork (DSN) memory 22, a retrieval DS processing unit 104, adistribution network 106, at least one distribution module 207, aplurality of set top boxes 1-V, and a plurality of viewers 1-V. The DSNmemory 22 includes a plurality of DS units 1-n. The distribution network106 may include one or more of a hybrid fiber coax system, a satellitesystem, an internet access system, and a wireless system. The set topboxes 1-V include the computing core 26 of FIG. 2 DS processing 34 toreceive/retrieve content slices, de-slice, and decode to produce thecontent for consumption (e.g., viewing).

The viewers 1-V may be implemented with a flat panel televisionincluding a display and speakers to reproduce content. As illustrated,the ingest DS processing unit 102 and the retrieval DS processing unit104 are implemented as at least two units. In another implementationexample, the ingest DS processing unit 102 and the retrieval DSprocessing unit 104 are implemented in the same unit. In yet anotherimplementation example, the ingest DS processing unit 102 and/or theretrieval DS processing unit 104 are implemented as part of at least oneof the set top boxes 1-V. In yet another implementation example, the DSNmemory 22 is implemented in one or more of the set top boxes 1-V. Thedistribution module 207 may be implemented utilizing the computer core26 of FIG. 2 and may further be implemented as an independent unit asillustrated, as part of the retrieval DS processing unit 104, and/or inone or more of the set top boxes 1-V serving a plurality of set topboxes.

The ingest DS processing unit 102 stores at least a portion of content108 in the DSN memory 22. The retrieval DS processing unit 104 retrievesat least a portion of the content 108 from the DSN memory 22 and sendsthe content 108 as retrieved slices 112 to the distribution module 207in response to retrieval requests 110. The distribution module 207decodes at least some of the retrieved slices 112 utilizing an errorcoding dispersal storage function to produce digital video 210. Thedistribution module 207 sends the digital video 210 to one or more ofthe set top boxes 1-V for consumption by one or more of the viewers 1-Vvia the distribution network 106. The viewers 1-V reproduce content(e.g., video, audio, pictures, web content) output from thecorresponding set top boxes 1-V. The set top boxes 1-V may select livebroadcast content (e.g., broadcast/multicast or on-demand video overcable, satellite and/or the internet) and/or stored content from the DSNmemory 22 via the distribution module 207 and/or the retrieval DSprocessing unit 104.

The set top boxes 1-V send commands to the distribution module 207. Thecommands include one or more of playback request 208, a record request,a pause request, a skip forward request, a skip backwards request, aselect broadcast content request, and a delete request. In an example ofoperation, the ingest DS processing unit 102 stores a portion of thecontent 108 in the DSN memory 22 in response to a record command fromset top box 6 (e.g., transferred from the distribution module 207). Settop box 6 sends a playback request 208 to the distribution module 207 toplayback the portion of the content 108. The distribution module 207sends a retrieval request 110 to the retrieval DS processing unit 104.Next, the retrieval DS processing unit 104 retrieves the portion of thecontent as retrieved slices 112 from the DSN memory 22 and sends theretrieved slices 112 to the destination module 207. The distributionmodule 207 decodes the retrieved slices 112 to produce digital video 210and sends the digital video 210 to the set top box 6. The set top box 6receives the digital video 210 and formats the video to produceformatted video in a format substantially compatible with viewer 6. Theset top box 6 sends the formatted video to viewer 6.

In another example of operation, the ingest DS processing unit 102determines which portion of the content 108 to store in the DSN memory22 for subsequent retrieval (e.g., immediately, minutes, hours, days,and even years later) and consumption by one or more of the set topboxes 1-V. Such a determination may be based on one or more of acommand, a command from the set top box, a command from the distributionmodule 207, a command from the retrieval DS processing unit 104, acommand from a DS managing unit, a DSN memory status indictor, and apredetermination. In an example, set top box 7 sends a record request tothe distribution module 207.

The distribution module 207 sends a record command to the ingest DSprocessing unit 102 identifying which portion of the content 108 tostore in the DSN memory 22. In another example, the ingest DS processing102 determines to store all of the received content 108 based on apredetermination. For instance, the ingest DS processing unit 102continuously stores all content 108 from a 500 channel cable TVdistribution system. The set top boxes 1-V may retrieve slices and/orcontent immediately and/or at a time much later than the originalreception of the content by the ingest DS processing unit 102. Forinstance, the set top boxes 1-V retrieve content from the DSN memory 22,via the distribution module 207 and the retrieval DS processing unit104, immediately after the content 108 was stored in the DSN memory 22to mimic broadcast reception. In another instance, the set top boxes 1-Vmay retrieve content from the DSN memory 22 hours, days, months, or evenyears after the content of 108 was stored in the DSN memory 22 to mimicdigital video recorder playback.

In another example of operation, the ingest DS processing unit 102determines to store content selected by one or more of the plurality ofset top boxes 1-V. For instance, set top box 2 sends a record command tothe distribution module 207 where the record command includes a commandto record the 5:30 pm evening news on cable channel 188 on October 18.The distribution module 207 sends a record command to the retrieval DSprocessing unit 104. The retrieval DS processing unit 104 communicatesthe record command to the ingest DS processing unit 102. The ingest DSprocessing unit 102 processes the record command which may includesaving the store command for future execution.

The ingest DS processing unit 102 executes the store command on October18 at 5:30 pm by selecting the content from cable channel 188, receivingthe content, determining write operational parameters (e.g., pillarwidth n, write threshold, encoding method, slicing method, encryptionmethod, etc.), encoding the content utilizing an error coded dispersedstorage function and in accordance with write operational parameters toproduce a plurality of sets of encoded data slices, determining which DSunits to store the plurality of sets of encoded data slices, and sendingthe plurality of sets of encoded data slices to the DSN memory 22 with astore command for storage in the selected DS units. Note that the ingestDS processing unit 102 determines the write operational parameters basedon one or more of a command, a command from the retrieval DS processingunit, an estimated number of store commands received for the samecontent indicator, a system performance indicator, a memory utilizationindicator, a policy indicator, a total population of set top boxesindicator, and a predetermination.

Note that multiple set top boxes may send the distribution module 207 arecord command specifying the same content portion. In an example, theingest DS processing unit 102 stores slices created from a contentportion in response to receiving at least one record command for thecontent portion from at least one set top box (e.g., via thedistribution module 207 and the retrieval DS processing unit 104). Theingest DS processing unit 102 determines if it has received recordcommands for the same content portion (e.g., check a table of pendingrecord operations) and processes the record commands in accordance withthe determination. In another example, the ingest DS processing unit 102queues the store command based on receiving a first record command forthe content portion and queues nothing when receiving a second recordcommand for the same content portion as the first record command. Inthis instance, the first record command for a given content portioninvokes storing the content as slices to the DSN memory 22 and any othersubsequent record commands for the same content do not change thestoring of that content portion as slices in the DSN memory 22.

In another example of operation, the ingest DS processing unit 102queues the store command based on receiving a first record command forthe content portion and queues another store command when receiving asecond (or subsequent) record command for the same content portion asthe first record command. For instance, the ingest DS processing unit102 determines different write operational parameters based on receivingtwo or more store commands for the same content portion. Such adetermination may be based on one or more of a command, a command fromthe retrieval DS processing unit, the number of store commands receivedfor the same content portion, a system performance indicator, a memoryutilization indicator, a policy indicator, a total population of set topboxes indicator, and a predetermination.

Note that the ingest DS processing unit 102 may receive a record/storecommand after the content (e.g., a live broadcast stream) has beenstarted to be received but before it has all been received (e.g., partway in a real time broadcast). The ingest DS processing unit 102 maydetermine the same or different write operational parameters for acontent recording in progress when an incremental record command forthat content is received.

The ingest DS processing unit 102 processes the record command (e.g.,from the viewer/set top box via the distribution module 207 and/or theretrieval DS processing unit 104) including determining read operationalparameters for the viewer for a content portion (e.g., pillar width n,which particular pillars are allowed to read, read threshold, decodingmethod, de-slicing method, decryption method, etc.). In an example, theingest DS processing unit 102 performs the determination when the ingestDS processing unit 102 receives the record command.

In another example, the distribution module 207 determines the readoperational parameters when the retrieval distribution module 207receives a playback request 208 from a viewer/set top box. In eitherexample, the determination may be based on one or more of a command, thenumber of store commands received for the same content portion, anestimated number of store commands received for the same content portionindicator, which combinations of pillars have already been assigned(e.g., the read operational parameters of other viewers), a systemperformance indicator, a cost indicator, a subscription level indicator,a reliability requirement, a reliability estimator, a memory utilizationindicator, a pillar availability indicator, a policy indicator, a totalpopulation of set top boxes indicator, and a predetermination. Forinstance, set top box 1 is assigned read operational parameters to readfrom pillars 1-10 and set top box 2 is assigned read operationalparameters to read from pillars 3-12 when the system has 16 pillars anda read threshold of 10 and both set top boxes have requested the samecontent portion. In another instance, each set top box is assigned morethan one set of combinations of allowed read pillars to improve readreliability. For example, the distribution module 207 may utilize one ormore of the allowed read pillar sets of the read operational parameters(e.g., for the particular set top box) to convert retrieved slices 112from the allowed read pillars into the desired content portion asdigital video 210.

FIG. 17B is a flowchart illustrating another example of retrievingcontent. In particular, a method is presented for use in conjunctionwith one or more functions and features described in conjunction withFIGS. 1-5, 17A, and also FIG. 17B. The method includes step 191 where aprocessing module of one or more computing devices of a centralizeddigital video storage (DVS) system regarding recording of broadcastmulti-media content that is to be broadcast at a particular broadcasttime, determines a number of subscriber devices that have selected torecord the multi-media content prior to the particular broadcast time,where the number of subscriber devices includes zero or more subscriberdevices.

At the particular broadcast time, the method continues at step 193 wherethe processing module receives the multi-media content as it is beingbroadcast. When the number of subscriber devices is equal to or greaterthan a first value, the method branches to step 203. When the number ofsubscriber devices is less than the first value, the method continues tostep 195.

The method continues at step 195 where the processing module dispersedstorage error encodes data segments of the multi-media content usingfirst level encoding parameters to produce sets of first level encodeddata slices when the number of subscriber devices is less than a firstvalue. One of the data segments is encoded to generate one set of thesets of first level encoded data slices. The first level encodingparameters includes a first pillar width number and a first decodethreshold number to provide a first plurality of combinations of a firstdecode threshold number of encoded data slices per data segment.

The method continues at step 197 where the processing module stores thesets of first level encoded data slices in a first set of storage unitsof the centralized DVS system. The method continues at step 199 wherethe processing module updates the number of subscriber devices duringthe broadcast of the multi-media content to include subscriber devicesthat requested recording of the multi-media content during the broadcastof the multi-media content to produce an updated number of subscriberdevices. When the number of subscriber devices is less than the firstvalue and the updated number of subscriber devices is equal to orgreater than the first value, the method continues at step 201 where theprocessing module dispersed storage error encodes remaining datasegments of the multi-media content using second level encodingparameters. The method branches to step 207.

Alternatively, or in addition to, when the number of subscriber devicesis less than the first value and the updated number of subscriberdevices is equal to or greater than the first value, the processingmodule re-encodes the data segments that were encoded using the firstencoding parameters using the second encoding parameters. The secondlevel encoding parameters includes a second pillar width number and asecond decode threshold number to provide a second plurality ofcombinations of a second decode threshold number of encoded data slicesper data segment.

Alternatively, or in addition to, when the number of subscriber units iszero, the processing module dispersed storage error encodes the datasegments of the multi-media content using default level encodingparameters to produce sets of default level encoded data slices. One ofthe data segments is encoded to generate one set of the sets of defaultlevel encoded data slices, where the default level encoding parametersprovides a lesser combination of decode threshold number of encoded dataslices per data segment than the first level encoding parameters. Theprocessing module stores the sets of default level encoded data slicesin storage units of the centralized DVS system. When a record enabletime period expires and the number of subscriber units that haveselected to record the multi-media content prior is zero, the processingmodule deletes the sets of default level encoded data slices from thestorage units.

When number of subscriber devices is equal to or greater than the firstvalue, the method continues at step 203 where the processing moduledispersed storage error encodes the data segments of the multi-mediacontent using the second level encoding parameters to produce sets ofsecond level encoded data slices. One of the data segments is encoded togenerate one set of the sets of second level encoded data slices, wherethe second level encoding parameters provides a greater combination ofdecode threshold number of encoded data slices per data segment than thefirst level encoding parameters.

The method continues at step 205 where the processing module stores thesets of second level encoded data slices in a second set of storageunits of the centralized DVS system. The first and second sets ofstorage units may be the same set of storage units or different sets ofstorage units.

Alternatively, or in addition to, when the number of subscriber devicesis equal to or greater than a second value, wherein the second value isgreater than the first value, the processing module dispersed storageerror encodes the data segments of the multi-media content using thirdlevel encoding parameters to produce sets of third level encoded dataslices. One of the data segments is encoded to generate one set of thesets of third level encoded data slices, where the third level encodingparameters provides a greater combination of decode threshold number ofencoded data slices per data segment than the second level encodingparameters. The processing module stores the sets of third level encodeddata slices in a third set of storage units of the centralized DVSsystem.

The method continues at step 207 where the processing module assignsunique retrieval combinations of encoded data slices to the subscriberdevices for enabling playback of a unique copy of the multi-mediacontent. After the broadcast of the multi-media content and prior toexpiration of a record enable time period, the method continues at step209 where the processing module updates the number of subscriber devicesto include subscriber devices that requested recording of themulti-media content to produce an updated number of subscriber devices.When the number of subscriber devices is less than the first value andthe updated number of subscriber devices is equal to or greater than thefirst value, the method continues at step 211 where the processingmodule re-encodes the data segments of the multi-media content using thesecond encoding parameters.

The method described above in conjunction with a processing module canalternatively be performed by other modules of a dispersed storagenetwork or by other devices. In addition, at least one memory sectionthat stores operational instructions can, when executed by one or moreprocessing modules of one or more computing devices of a dispersedstorage network (DSN), cause the one or more computing devices toperform any or all of the method steps described above.

FIG. 18A is a flowchart illustrating another example of retrievingcontent. The method begins with step 212 were a processing module (e.g.,of a retrieval dispersed storage (DS) processing unit) receives acontent retrieval message from a requester. The requester may include aset top box, a user device, a storage integrity processing unit, a DSmanaging unit, another DS processing unit, and/or a DS unit. The contentretrieval message may include one or more of a content identifier (ID),a user ID, digital rights management (DRM) information, a DRM policy,read operational parameters, and a content type indicator.

The method continues at step 214 where the processing module determinespreviously assigned pillar combinations where the pillar combinationsinclude sets of DS unit pillars that may be utilized to retrievepreviously stored slices of the requested content. Such a determinationmay be based on one or more of the content ID, the user ID, a vaultlookup, a pillar combination table lookup, DRM information, a DRMpolicy, read operational parameters, system parameters, and a contenttype indicator.

The method continues at step 216 where the processing module determinesservice-level requirements, which may include cost requirements,availability requirements, reliability requirements, performancerequirements, and/or combinations of requirements. In an example, a usermay require highly reliable retrievals where the cost is not important.In another example the user may require the lowest cost possible and iswilling to sacrifice reliability. Such a determination may be based onone or more of the content of the content retrieval message, content ID,the user ID, a vault lookup, a pillar combination table lookup, DRMinformation, a DRM policy, read operational parameters, systemparameters, and a content type indicator.

The method continues at step 218 where the processing module determinespillar combinations, which may include one or more unique sets ofcombination of pillars to retrieve slices from. Such a determination maybe based on one or more of the user ID, a vault lookup, a pillarcombination table lookup, previously assigned pillars, write operationalparameters utilized when the content was stored in the DS and memory,the content of the content retrieval message, content ID, DRMinformation, a DRM policy, read operational parameters, systemparameters, and a content type indicator. In an example, the retrievalprocessing module assigns the read pillar combinations for a first timeto the requester. In another example the processing module is recallingthe read pillar combinations for the second or greater time for the samerequester.

Note that there are many possible ways to allocate pillar combinations.For example, when the pillar width is 32 and the read threshold is 24there are over 10 million ways to choose 24 pillars out of 32 pillars.For instance, 10,000 users may be assigned an average of 1000 pillarcombinations each to provide a certain level of retrieval reliability.In some cases a user may be assigned just five pillar combinations whilein another case a user may be assigned 5000 pillar combinations based onone or more of service-level requirements, pillar combinationavailability, and service tiers and pricing levels.

The method continues at step 220 where the processing module determinesthe read operational parameters which may include one or more of apillar width, read threshold, write threshold, pillars allowed toretrieve from, a decode method, a de-sliced method, a decryption method,and a decryption key. Note that the pillar combinations may be uniqueand specific to the requester if access to the content is restricted.Such a determination may be based on one or more of a user ID, a vaultlookup, a pillar combination table lookup, previously assigned pillars,write operational parameters utilized when the content was stored in theDSN memory, the content of the content retrieval message, content ID,DRM information, a DRM policy, the read operational parameters, systemparameters, and a content type indicator.

The method continues at step 222 where the processing module retrieves aplurality of encoded data slices from the DSN memory in accordance withthe read operational parameters, the allowed pillar combinations, and/orthe DRM policy. In an example, the processing module decodes a set ofencoded data slices of the plurality of encoded data slices using anerror coding dispersed storage function and the read operationalparameters to produce a data segment. The processing module continues todecode more sets to produce more segments. The processing moduletemporarily saves each of the data segments until they are allretrieved. In another example, the retrieval processing moduletemporarily saves each of the retrieved encoded data slices (e.g., atleast a read threshold) for each of the data segments as they areretrieved until slices from all of the data segments are retrieved.

The method continues at step 224 where the processing module determineswhether all of the data segments have been retrieved based on one ormore of the read operational parameters, a content size indicator, anddata segments reproduced so far. The method branches to step 228 whenthe processing module determines that all segments have been retrieved.The method continues to step 226 where the processing module determinesthat all segments have not been retrieved. The method continues at step226 where the processing module selects the next segment and the methodrepeats back to step 222. Note that the processing module utilizes thesame read operational parameters and pillar combinations for each datasegment. The method continues at step 228 where the processing moduleaggregates the data segments to recreate a content portion. The methodcontinues at step 230 where the processing module sends the contentportion and/or the encoded data slices of each data segment to therequester.

FIG. 18B is a flowchart illustrating another example of retrievingcontent. In particular, a method is presented for use in conjunctionwith one or more functions and features described in conjunction withFIGS. 1-5, 18A, and also FIG. 18B. The method includes step 215 where aprocessing module of one or more computing devices of a centralizeddigital video storage (DVS) system that supports a plurality ofsubscriber units, stores, for playback, a plurality of sets of encodeddata slices in storage units of the centralized DVS system. Multi-mediacontent is dispersed storage error encoded using a pillar width numberof “n” and a decode threshold number of “k” to produce the plurality ofsets of encoded data slices where “n” and “k” provide a certain numberof unique combinations of the decode threshold number of encoded dataslices per set of encoded data slices of the plurality of sets ofencoded data slices.

The method continues at step 217 where the processing module monitorsthe storage units for a failure mode. The method continues at step 219where the processing module monitors a number of subscriber devicesrequesting at least partially concurrent playback of the multi-mediacontent.

The method continues at step 221 where the processing module determinesbased on a number of the storage units in the failure mode, the pillarwidth number and the decode threshold number, and the number ofsubscriber devices whether a sufficient number of the uniquecombinations exists to service playback of the multi-media content forthe number of subscriber devices. As a specific example of thedetermining whether the sufficient number of the unique combinationsexists, the processing module calculates available unique combinationsof the decode threshold number of encoded data slices per set of encodeddata slices of the plurality of sets of encoded data slices based on thestorage units that are on line and storage of encoded data slices of theplurality of sets of encoded data slices in the storage units that areon line. The processing module ascertains a desired number for a set ofunique combinations to assign to each of the subscriber devices. Whenthe number of available unique combinations is less than a product ofthe desired number and the number of subscriber devices, the processingmodule determines that the sufficient number of the unique combinationsdoes not exist.

As another specific example of the determining whether the sufficientnumber of the unique combinations exists comprises, the processingmodule calculates available unique combinations of the decode thresholdnumber of encoded data slices per set of encoded data slices of theplurality of sets of encoded data slices based on the storage units thatare on line and storage of encoded data slices of the plurality of setsof encoded data slices in the storage units that are on line. For eachsubscriber device having a first subscription priority level, theprocessing module ascertains a first level number of unique combinationsassigned to each of the subscriber devices. For each subscriber devicehaving a second subscription priority level, the processing moduleascertains a second level number of unique combinations assigned to eachof the subscriber devices, where the second level number is less thanthe first level number and the second subscription priority level isless than the first subscription priority level.

When the number of available unique combinations is less than a sum of afirst product and a second product, the processing module determinesthat the sufficient number of the unique combinations does not exist,where the first product is of the first level number and the number ofsubscriber devices having the first subscription priority level and thesecond product is of the second level number and the number ofsubscriber devices having the second subscription priority level.

When the sufficient number of the unique combinations do not exist toservice the playback of the multi-media content for the number ofsubscriber devices, the method continues at step 223 where theprocessing module reassigns unique combinations of the decode thresholdnumber of encoded data slices per set of encoded data slices of theplurality of sets of encoded data slices to some of the subscriberdevices based on subscription priority level such that reliable playbackservice of the multi-media content is provided to the some of thesubscriber devices. As a specific example of the reassigning of theunique combinations of the decode threshold number of encoded dataslices, the processing module, for each subscriber device having a firstsubscription priority level, allocates the desired number of availableunique combinations to the subscriber device.

As another specific example of the reassigning of the uniquecombinations of the decode threshold number of encoded data slices, theprocessing module, for each subscriber device having the firstsubscription priority level, allocates the first level number ofavailable unique combinations to the subscriber device having the firstsubscription priority level. For each subscriber device having thesecond subscription priority level, the processing module allocates,when available, at least one available unique combination to thesubscriber device having the second subscription priority level.

Alternatively, or in addition to, when one of the storage units in thefailure mode comes back on line during playback of the multi-mediacontent, the processing module calculates newly available uniquecombinations of the decode threshold number of encoded data slices perset of encoded data slices of the plurality of sets of encoded dataslices based on the storage units that are currently on line and storageof encoded data slices of the plurality of sets of encoded data slicesin the storage units that are on line. The processing module allocatesat least some of the newly available unique combinations to at least onesubscriber device that was having less than reliable playback service ofthe multi-media content.

The method continues at step 225 where the processing module sends theunique combinations of the decode threshold number of encoded dataslices per set of encoded data slices of the plurality of sets ofencoded data slices to the some of the subscriber devices. The methoddescribed above in conjunction with a processing module canalternatively be performed by other modules of a dispersed storagenetwork or by other devices. In addition, at least one memory sectionthat stores operational instructions can, when executed by one or moreprocessing modules of one or more computing devices of a dispersedstorage network (DSN), cause the one or more computing devices toperform any or all of the method steps described above.

FIG. 19 is another flowchart illustrating another example of retrievingcontent. The method begins with step 232 where a processing module(e.g., of a retrieval dispersed storage (DS) processing unit) receives acontent retrieval message from a requester. The requester may include aset top box, a user device, a storage integrity processing unit, a DSmanaging unit, another DS processing unit, and/or a DS unit. The contentretrieval message may include one or more of a content identifier (ID),a user ID, digital rights management (DRM) information, a DRM policy,read operational parameters, and a content type indicator.

The method continues at step 234 where the processing module determinespreviously assigned pillar combinations where the pillar combinationsinclude sets of DS unit pillars that may be utilized to retrievepreviously stored slices of the requested content. Such a determinationmay be based on one or more of the content ID, a user ID, a vaultlookup, a pillar combination table lookup, DRM information, a DRMpolicy, read operational parameters, system parameters, and a contenttype indicator.

The method continues at step 236, where the processing module determinesservice-level requirements, which may include cost requirements,availability requirements, reliability requirements, performancerequirements, and/or combinations of requirements. In an example, a usermay require highly reliable retrievals where the cost is not important.In another example the user may require the lowest cost possible and iswilling to sacrifice reliability. Such a determination may be based onone or more of content of the content retrieval message, a content ID, auser ID, a vault lookup, a pillar combination table lookup, DRMinformation, a DRM policy, read operational parameters, systemparameters, and a content type indicator.

The method continues at step 238 where the processing module determinespillar combinations for data segment of the requested content, which mayinclude one or more unique sets of combination of pillars to retrieveslices from. Such a determination may be based on one or more of a userID, a vault lookup, a pillar combination table lookup, previouslyassigned pillars, previously utilized pillar combination by this userID, a list of data segments and pillar combinations, a data segment ID,write operational parameters utilized when the content was stored in adispersed storage network (DSN) memory, content of the content retrievalmessage, content ID, DRM information, a DRM policy, read operationalparameters, system parameters, and a content type indicator. In anexample, the processing module assigns the read pillar combinations fora first time to the requester. In another example, the processing moduleis recalling the read pillar combinations for a second or greater timefor the same requester.

Note that there are many possible ways to allocate pillar combinations.For example, when the pillar width is 32 and the read threshold is 24there are over 10 million ways to choose 24 pillars out of 32 pillars.For instance, 10,000 users may be assigned an average of 1000 pillarcombination each to provide a certain level of retrieval reliability. Insome cases a user may be assigned just five pillar combinations while inanother case a user may be assigned 5000 pillar combinations based onone or more of service-level requirements, pillar combinationavailability, and/or service tiers and pricing levels. In an embodiment,each data segment utilizes a different set of pillar combinations tofurther improve the security if restricted access content.

The method continues at step 240 where the processing module determinesread operational parameters which may include a pillar width, readthreshold, write threshold, pillars allowed to retrieve from, the decodemethod, the de-sliced method, decryption method, and/or the decryptionkey. Note that the pillar combinations may be unique and specific to therequester if access to the content is restricted. Such a determinationmay be based on one or more of a user ID, a vault lookup, a pillarcombination table lookup, previously assigned pillars, write operationalparameters utilized when the content was stored in the DS and memory,the content of the content retrieval message, content ID, DRMinformation, a DRM policy, the read operational parameters, systemparameters, and a content type indicator.

The method continues at step 242 where the processing module retrieves aplurality of sets of encoded data slices corresponding to each datasegment from the DSN memory in accordance with the read operationalparameters, the allowed pillar combinations for the current datasegment, and/or the DRM policy. In an example, the processing moduledecodes a set of the plurality of sets of encoded data slices using anderror coding dispersal storage function and in accordance with the readoperational parameters to produce a data segment. The processing moduledecodes more segments from more sets of the plurality of encoded dataslices and temporarily saves each of the reproduced data segments untilthey are all retrieved. In another example, the processing moduletemporarily saves each of the retrieved encoded data slices (e.g., atleast a read threshold) corresponding to each of the data segments asthey are retrieved until encoded data slices from all of the datasegments are retrieved.

The method continues at step 244 where the processing module determinesif all of the data segments have been retrieved based on one or more ofthe read operational parameters, a content size indicator, and/or datasegments retrieved so far. The method branches to step 248 when theprocessing module determines that all of the data segments have beenretrieved. The method continues to step 246 when the processing moduledetermines that all of the data segments have not been retrieved. Themethod continues at step 246 where the processing module goes to thenext data segment and the method repeats back to step 238. Note that theprocessing module may utilize different read operational parameters anddifferent pillar combinations for each data segment. The methodcontinues at step 248 where the processing module aggregates the datasegments to recreate a content portion. The method continues at step 250where the processing module sends the content portion and/or the encodeddata slices of each data segment to the requester.

As may be used herein, the terms “substantially” and “approximately”provides an industry-accepted tolerance for its corresponding termand/or relativity between items. Such an industry-accepted toleranceranges from less than one percent to fifty percent and corresponds to,but is not limited to, component values, integrated circuit processvariations, temperature variations, rise and fall times, and/or thermalnoise. Such relativity between items ranges from a difference of a fewpercent to magnitude differences. As may also be used herein, theterm(s) “operably coupled to”, “coupled to”, and/or “coupling” includesdirect coupling between items and/or indirect coupling between items viaan intervening item (e.g., an item includes, but is not limited to, acomponent, an element, a circuit, and/or a module) where, for indirectcoupling, the intervening item does not modify the information of asignal but may adjust its current level, voltage level, and/or powerlevel. As may further be used herein, inferred coupling (i.e., where oneelement is coupled to another element by inference) includes direct andindirect coupling between two items in the same manner as “coupled to”.As may even further be used herein, the term “operable to” or “operablycoupled to” indicates that an item includes one or more of powerconnections, input(s), output(s), etc., to perform, when activated, oneor more its corresponding functions and may further include inferredcoupling to one or more other items. As may still further be usedherein, the term “associated with”, includes direct and/or indirectcoupling of separate items and/or one item being embedded within anotheritem. As may be used herein, the term “compares favorably”, indicatesthat a comparison between two or more items, signals, etc., provides adesired relationship. For example, when the desired relationship is thatsignal 1 has a greater magnitude than signal 2, a favorable comparisonmay be achieved when the magnitude of signal 1 is greater than that ofsignal 2 or when the magnitude of signal 2 is less than that of signal1.

The present invention has also been described above with the aid ofmethod steps illustrating the performance of specified functions andrelationships thereof. The boundaries and sequence of these functionalbuilding blocks and method steps have been arbitrarily defined hereinfor convenience of description. Alternate boundaries and sequences canbe defined so long as the specified functions and relationships areappropriately performed. Any such alternate boundaries or sequences arethus within the scope and spirit of the claimed invention.

The present invention has been described, at least in part, in terms ofone or more embodiments. An embodiment of the present invention is usedherein to illustrate the present invention, an aspect thereof, a featurethereof, a concept thereof, and/or an example thereof. A physicalembodiment of an apparatus, an article of manufacture, a machine, and/orof a process that embodies the present invention may include one or moreof the aspects, features, concepts, examples, etc. described withreference to one or more of the embodiments discussed herein.

The present invention has been described above with the aid offunctional building blocks illustrating the performance of certainsignificant functions. The boundaries of these functional buildingblocks have been arbitrarily defined for convenience of description.Alternate boundaries could be defined as long as the certain significantfunctions are appropriately performed. Similarly, flow diagram blocksmay also have been arbitrarily defined herein to illustrate certainsignificant functionality. To the extent used, the flow diagram blockboundaries and sequence could have been defined otherwise and stillperform the certain significant functionality. Such alternatedefinitions of both functional building blocks and flow diagram blocksand sequences are thus within the scope and spirit of the claimedinvention. One of average skill in the art will also recognize that thefunctional building blocks, and other illustrative blocks, modules andcomponents herein, can be implemented as illustrated or by discretecomponents, application specific integrated circuits, processorsexecuting appropriate software and the like or any combination thereof.

What is claimed is:
 1. A method for execution by one or more computingdevices of a centralized digital video storage (DVS) system regardingrecording of broadcast multi-media content that is to be broadcast at aparticular broadcast time, the method comprises: determining a number ofsubscriber devices that have selected to record the multi-media contentprior to the particular broadcast time, wherein the number of subscriberdevices includes zero or more subscriber devices; and at the particularbroadcast time: receiving the multi-media content as it is beingbroadcast; when the number of subscriber devices is less than a firstvalue: dispersed storage error encoding data segments of the multi-mediacontent using first level encoding parameters to produce sets of firstlevel encoded data slices, wherein one of the data segments is encodedto generate one set of the sets of first level encoded data slices; andstoring the sets of first level encoded data slices in a first set ofstorage units of the centralized DVS system; and when the number ofsubscriber devices is equal to or greater than the first value:dispersed storage error encoding the data segments of the multi-mediacontent using second level encoding parameters to produce sets of secondlevel encoded data slices, wherein one of the data segments is encodedto generate one set of the sets of second level encoded data slices,wherein the second level encoding parameters provides a greatercombination of decode threshold number of encoded data slices per datasegment than the first level encoding parameters; and storing the setsof second level encoded data slices in a second set of storage units ofthe centralized DVS system.
 2. The method of claim 1 further comprises:updating the number of subscriber devices during the broadcast of themulti-media content to include subscriber devices that requestedrecording of the multi-media content during the broadcast of themulti-media content to produce an updated number of subscriber devices;and when the number of subscriber devices is less than the first valueand the updated number of subscriber devices is equal to or greater thanthe first value, dispersed storage error encoding remaining datasegments of the multi-media content using the second level encodingparameters.
 3. The method of claim 2 further comprises: when the numberof subscriber devices is less than the first value and the updatednumber of subscriber devices is equal to or greater than the firstvalue, re-encoding the data segments that were encoded using the firstlevel encoding parameters using the second level encoding parameters. 4.The method of claim 1 further comprises: assigning unique retrievalcombinations of encoded data slices to the subscriber devices forenabling playback of a unique copy of the multi-media content.
 5. Themethod of claim 1 further comprises: after the broadcast of themulti-media content and prior to expiration of a record enable timeperiod, updating the number of subscriber devices to include subscriberdevices that requested recording of the multi-media content to producean updated number of subscriber devices; and when the number ofsubscriber devices is less than the first value and the updated numberof subscriber devices is equal to or greater than the first value,re-encoding the data segments of the multi-media content using thesecond level encoding parameters.
 6. The method of claim 1 furthercomprises: when the number of subscriber devices is equal to or greaterthan a second value, wherein the second value is greater than the firstvalue: dispersed storage error encoding the data segments of themulti-media content using third level encoding parameters to producesets of third level encoded data slices, wherein one of the datasegments is encoded to generate one set of the sets of third levelencoded data slices, wherein the third level encoding parametersprovides a greater combination of decode threshold number of encodeddata slices per data segment than the second level encoding parameters;and storing the sets of third level encoded data slices in a third setof storage units of the centralized DVS system.
 7. The method of claim 1further comprises: the first level encoding parameters includes a firstpillar width number and a first decode threshold number to provide afirst plurality of combinations of a first decode threshold number ofencoded data slices per data segment; and the second level encodingparameters includes a second pillar width number and a second decodethreshold number to provide a second plurality of combinations of asecond decode threshold number of encoded data slices per data segment.8. The method of claim 1 further comprises: when a number of subscriberunits is zero: dispersed storage error encoding the data segments of themulti-media content using default level encoding parameters to producesets of default level encoded data slices, wherein one of the datasegments is encoded to generate one set of the sets of default levelencoded data slices, wherein the default level encoding parametersprovides a lesser combination of decode threshold number of encoded dataslices per data segment than the first level encoding parameters; andstoring the sets of default level encoded data slices in storage unitsof the centralized DVS system.
 9. The method of claim 8 furthercomprises: when a record enable time period expires and the number ofsubscriber units that have selected to record the multi-media contentprior is zero, deleting the sets of default level encoded data slicesfrom the storage units.
 10. A non-transitory computer readable storagemedium comprises: at least one memory section that stores operationalinstructions that, when executed by one or more processing modules ofone or more computing devices of a centralized digital video storage(DVS) system regarding recording of multi-media content that is to bebroadcast at a particular broadcast time, causes the one or morecomputing devices to: determine a number of subscriber devices that haveselected to record the multi-media content prior to the particularbroadcast time, wherein the number of subscriber devices includes zeroor more subscriber devices; and at the particular broadcast time:receive the multi-media content as it is being broadcast; when thenumber of subscriber devices is less than a first value: dispersedstorage error encode data segments of the multi-media content usingfirst level encoding parameters to produce sets of first level encodeddata slices, wherein one of the data segments is encoded to generate oneset of the sets of first level encoded data slices; and store the setsof first level encoded data slices in a first set of storage units ofthe centralized DVS system; and when the number of subscriber devices isequal to or greater than the first value: dispersed storage error encodethe data segments of the multi-media content using second level encodingparameters to produce sets of second level encoded data slices, whereinone of the data segments is encoded to generate one set of the sets ofsecond level encoded data slices, wherein the second level encodingparameters provides a greater combination of decode threshold number ofencoded data slices per data segment than the first level encodingparameters; and store the sets of second level encoded data slices in asecond set of storage units of the centralized DVS system.
 11. Thenon-transitory computer readable storage medium of claim 10 furthercomprises: the at least one memory section stores further operationalinstructions that, when executed by the one or more processing modules,causes the one or more computing devices of the centralized DVS systemto: update the number of subscriber devices during the broadcast of themulti-media content to include subscriber devices that requestedrecording of the multi-media content during the broadcast of themulti-media content to produce an updated number of subscriber devices;and when the number of subscriber devices is less than the first valueand the updated number of subscriber devices is equal to or greater thanthe first value, dispersed storage error encode remaining data segmentsof the multi-media content using the second level encoding parameters.12. The non-transitory computer readable storage medium of claim 11further comprises: the at least one memory section stores furtheroperational instructions that, when executed by the one or moreprocessing modules, causes the one or more computing devices of thecentralized DVS system to: when the number of subscriber devices is lessthan the first value and the updated number of subscriber devices isequal to or greater than the first value, re-encode the data segmentsthat were encoded using the first level encoding parameters using thesecond level encoding parameters.
 13. The non-transitory computerreadable storage medium of claim 10 further comprises: the at least onememory section stores further operational instructions that, whenexecuted by the one or more processing modules, causes the one or morecomputing devices of the centralized DVS system to: assign uniqueretrieval combinations of encoded data slices to the subscriber devicesfor enabling playback of a unique copy of the multi-media content. 14.The non-transitory computer readable storage medium of claim 10 furthercomprises: the at least one memory section stores further operationalinstructions that, when executed by the one or more processing modules,causes the one or more computing devices of the centralized DVS systemto: after the broadcast of the multi-media content and prior toexpiration of a record enable time period, update the number ofsubscriber devices to include subscriber devices that requestedrecording of the multi-media content to produce an updated number ofsubscriber devices; and when the number of subscriber devices is lessthan the first value and the updated number of subscriber devices isequal to or greater than the first value, re-encode the data segments ofthe multi-media content using the second level encoding parameters. 15.The non-transitory computer readable storage medium of claim 10 furthercomprises: the at least one memory section stores further operationalinstructions that, when executed by the one or more processing modules,causes the one or more computing devices of the centralized DVS systemto: when the number of subscriber devices is equal to or greater than asecond value, wherein the second value is greater than the first value:dispersed storage error encode the data segments of the multi-mediacontent using third level encoding parameters to produce sets of thirdlevel encoded data slices, wherein one of the data segments is encodedto generate one set of the sets of third level encoded data slices,wherein the third level encoding parameters provides a greatercombination of decode threshold number of encoded data slices per datasegment than the second level encoding parameters; and store the sets ofthird level encoded data slices in a third set of storage units of thecentralized DVS system.
 16. The non-transitory computer readable storagemedium of claim 10 further comprises: the first level encodingparameters includes a first pillar width number and a first decodethreshold number to provide a first plurality of combinations of a firstdecode threshold number of encoded data slices per data segment; and thesecond level encoding parameters includes a second pillar width numberand a second decode threshold number to provide a second plurality ofcombinations of a second decode threshold number of encoded data slicesper data segment.
 17. The non-transitory computer readable storagemedium of claim 10 further comprises: the at least one memory sectionstores further operational instructions that, when executed by the oneor more processing modules, causes the one or more computing devices ofthe centralized DVS system to: when a number of subscriber units iszero: dispersed storage error encode the data segments of themulti-media content using default level encoding parameters to producesets of default level encoded data slices, wherein one of the datasegments is encoded to generate one set of the sets of default levelencoded data slices, wherein the default level encoding parametersprovides a lesser combination of decode threshold number of encoded dataslices per data segment than the first level encoding parameters; andstore the sets of default level encoded data slices in storage units ofthe centralized DVS system.
 18. The non-transitory computer readablestorage medium of claim 17 further comprises: the at least one memorysection stores further operational instructions that, when executed bythe one or more processing modules, causes the one or more computingdevices of the centralized DVS system to: when a record enable timeperiod expires and the number of subscriber units that have selected torecord the multi-media content prior is zero, delete the sets of defaultlevel encoded data slices from the storage units.
 19. A computing deviceof a centralized digital video storage (DVS) system regarding recordingof multi-media content that is to be broadcast at a particular broadcasttime, the computing device comprises: an interface; and a processingmodule operably coupled to the interface, wherein the processing moduleis operable to: determine a number of subscriber devices that haveselected to record the multi-media content prior to the particularbroadcast time, wherein the number of subscriber devices includes zeroor more subscriber devices; and at the particular broadcast time:receive, via the interface, the multi-media content as it is beingbroadcast; when the number of subscriber devices is less than a firstvalue: dispersed storage error encode data segments of the multi-mediacontent using first level encoding parameters to produce sets of firstlevel encoded data slices, wherein one of the data segments is encodedto generate one set of the sets of first level encoded data slices; andstore, via the interface, the sets of first level encoded data slices ina first set of storage units of the centralized DVS system; and when thenumber of subscriber devices is equal to or greater than the firstvalue: dispersed storage error encode the data segments of themulti-media content using second level encoding parameters to producesets of second level encoded data slices, wherein one of the datasegments is encoded to generate one set of the sets of second levelencoded data slices, wherein the second level encoding parametersprovides a greater combination of decode threshold number of encodeddata slices per data segment than the first level encoding parameters;and store, via the interface, the sets of second level encoded dataslices in a second set of storage units of the centralized DVS system.20. The computing device of claim 19 further comprises: the processingmodule is further operable to: update the number of subscriber devicesduring the broadcast of the multi-media content to include subscriberdevices that requested recording of the multi-media content during thebroadcast of the multi-media content to produce an updated number ofsubscriber devices; and when the number of subscriber devices is lessthan the first value and the updated number of subscriber devices isequal to or greater than the first value, dispersed storage error encoderemaining data segments of the multi-media content using the secondlevel encoding parameters.
 21. The computing device of claim 20 furthercomprises: the processing module is further operable to: when the numberof subscriber devices is less than the first value and the updatednumber of subscriber devices is equal to or greater than the firstvalue, re-encode the data segments that were encoded using the firstlevel encoding parameters using the second level encoding parameters.22. The computing device of claim 19 further comprises: the processingmodule is further operable to: assign unique retrieval combinations ofencoded data slices to the subscriber devices for enabling playback of aunique copy of the multi-media content.
 23. The computing device ofclaim 19 further comprises: the processing module is further operableto: after the broadcast of the multi-media content and prior toexpiration of a record enable time period, update the number ofsubscriber devices to include subscriber devices that requestedrecording of the multi-media content to produce an updated number ofsubscriber devices; and when the number of subscriber devices is lessthan the first value and the updated number of subscriber devices isequal to or greater than the first value, re-encode the data segments ofthe multi-media content using the second level encoding parameters. 24.The computing device of claim 19 further comprises: the processingmodule is further operable to: when the number of subscriber devices isequal to or greater than a second value, wherein the second value isgreater than the first value: dispersed storage error encode the datasegments of the multi-media content using third level encodingparameters to produce sets of third level encoded data slices, whereinone of the data segments is encoded to generate one set of the sets ofthird level encoded data slices, wherein the third level encodingparameters provides a greater combination of decode threshold number ofencoded data slices per data segment than the second level encodingparameters; and store, via the interface, the sets of third levelencoded data slices in a third set of storage units of the centralizedDVS system.
 25. The computing device of claim 19 further comprises: thefirst level encoding parameters includes a first pillar width number anda first decode threshold number to provide a first plurality ofcombinations of a first decode threshold number of encoded data slicesper data segment; and the second level encoding parameters includes asecond pillar width number and a second decode threshold number toprovide a second plurality of combinations of a second decode thresholdnumber of encoded data slices per data segment.
 26. The computing deviceof claim 19 further comprises: the processing module is further operableto: when a number of subscriber units is zero: dispersed storage errorencode the data segments of the multi-media content using default levelencoding parameters to produce sets of default level encoded dataslices, wherein one of the data segments is encoded to generate one setof the sets of default level encoded data slices, wherein the defaultlevel encoding parameters provides a lesser combination of decodethreshold number of encoded data slices per data segment than the firstlevel encoding parameters; and store, via the interface, the sets ofdefault level encoded data slices in storage units of the centralizedDVS system.
 27. The computing device of claim 26 further comprises: theprocessing module is further operable to: when a record enable timeperiod expires and the number of subscriber units that have selected torecord the multi-media content prior is zero, delete the sets of defaultlevel encoded data slices from the storage units.